diff --git a/src/boxes/array/mod.rs b/src/boxes/array/mod.rs
index 00760d3d..7762b9de 100644
--- a/src/boxes/array/mod.rs
+++ b/src/boxes/array/mod.rs
@@ -1,34 +1,270 @@
-//! ArrayBox 📦 - 配列・リスト操作（両者一致！）
-// Nyashの箱システムによる配列・リスト操作を提供します。
-// 参考: 既存Boxの設計思想
+/*! 📦 ArrayBox - 配列・リスト操作Box
+ * 
+ * ## 📝 概要
+ * 順序付きコレクションを扱うためのBox。
+ * JavaScript風の配列操作APIで直感的なデータ管理が可能。
+ * 
+ * ## 🛠️ 利用可能メソッド
+ * - `push(item)` - 要素を末尾に追加
+ * - `pop()` - 末尾の要素を削除して返す
+ * - `get(index)` - 指定インデックスの要素を取得
+ * - `set(index, value)` - 指定インデックスに要素を設定
+ * - `length()` - 配列の長さを取得
+ * - `remove(index)` - 指定インデックスの要素を削除
+ * - `indexOf(item)` - 要素のインデックスを検索
+ * - `contains(item)` - 要素が含まれているか確認
+ * - `clear()` - すべての要素を削除
+ * - `join(separator)` - 文字列として結合
+ * 
+ * ## 💡 使用例
+ * ```nyash
+ * local arr, item
+ * arr = new ArrayBox()
+ * 
+ * // 要素の追加
+ * arr.push("Apple")
+ * arr.push("Banana")
+ * arr.push("Cherry")
+ * 
+ * // 要素へのアクセス
+ * print(arr.get(0))           // "Apple"
+ * print(arr.length())         // 3
+ * 
+ * // 要素の削除
+ * item = arr.pop()            // "Cherry"
+ * arr.remove(0)               // "Apple"削除
+ * 
+ * // 文字列結合
+ * print(arr.join(", "))       // "Banana"
+ * ```
+ * 
+ * ## 🎮 実用例 - TodoList
+ * ```nyash
+ * static box TodoList {
+ *     init { items, console }
+ *     
+ *     main() {
+ *         me.items = new ArrayBox()
+ *         me.console = new ConsoleBox()
+ *         
+ *         me.addTask("Nyash開発")
+ *         me.addTask("ドキュメント作成")
+ *         me.addTask("テスト実行")
+ *         
+ *         me.showTasks()
+ *     }
+ *     
+ *     addTask(task) {
+ *         me.items.push(task)
+ *         me.console.log("✅ タスク追加: " + task)
+ *     }
+ *     
+ *     showTasks() {
+ *         me.console.log("=== Todo List ===")
+ *         local i
+ *         i = 0
+ *         loop(i < me.items.length()) {
+ *             me.console.log((i + 1) + ". " + me.items.get(i))
+ *             i = i + 1
+ *         }
+ *     }
+ * }
+ * ```
+ * 
+ * ## ⚠️ 注意
+ * - インデックスは0から開始
+ * - 範囲外のインデックスアクセスはNullBoxを返す
+ * - 異なる型の要素を混在可能（Everything is Box）
+ */
 
+use crate::box_trait::{NyashBox, StringBox, IntegerBox, BoolBox};
+use crate::boxes::null_box::NullBox;
+use std::any::Any;
+use std::fmt::{Debug, Display};
+use std::sync::{Arc, Mutex};
+
+#[derive(Debug, Clone)]
 pub struct ArrayBox {
-    pub items: Vec<Box<dyn std::any::Any>>,
+    items: Arc<Mutex<Vec<Box<dyn NyashBox>>>>,
+    id: u64,
 }
 
 impl ArrayBox {
-    /// 新しいArrayBoxを作成
     pub fn new() -> Self {
-        ArrayBox { items: Vec::new() }
+        static mut COUNTER: u64 = 0;
+        let id = unsafe {
+            COUNTER += 1;
+            COUNTER
+        };
+        
+        ArrayBox { 
+            items: Arc::new(Mutex::new(Vec::new())),
+            id,
+        }
     }
-    /// 要素を追加
-    pub fn push(&mut self, item: Box<dyn std::any::Any>) {
-        self.items.push(item);
+    
+    /// 要素を末尾に追加
+    pub fn push(&self, item: Box<dyn NyashBox>) -> Box<dyn NyashBox> {
+        self.items.lock().unwrap().push(item);
+        Box::new(StringBox::new("ok"))
     }
+    
+    /// 末尾の要素を削除して返す
+    pub fn pop(&self) -> Box<dyn NyashBox> {
+        match self.items.lock().unwrap().pop() {
+            Some(item) => item,
+            None => Box::new(NullBox::new()),
+        }
+    }
+    
     /// 要素数を取得
-    pub fn len(&self) -> usize {
-        self.items.len()
+    pub fn length(&self) -> Box<dyn NyashBox> {
+        Box::new(IntegerBox::new(self.items.lock().unwrap().len() as i64))
     }
-    /// 要素を取得
-    pub fn get(&self, index: usize) -> Option<&Box<dyn std::any::Any>> {
-        self.items.get(index)
-    }
-    /// 要素を削除
-    pub fn remove(&mut self, index: usize) -> Option<Box<dyn std::any::Any>> {
-        if index < self.items.len() {
-            Some(self.items.remove(index))
+    
+    /// 指定インデックスの要素を取得
+    pub fn get(&self, index: Box<dyn NyashBox>) -> Box<dyn NyashBox> {
+        if let Some(idx_box) = index.as_any().downcast_ref::<IntegerBox>() {
+            let idx = idx_box.value as usize;
+            let items = self.items.lock().unwrap();
+            match items.get(idx) {
+                Some(item) => item.clone_box(),
+                None => Box::new(NullBox::new()),
+            }
         } else {
-            None
+            Box::new(StringBox::new("Error: get() requires integer index"))
+        }
+    }
+    
+    /// 指定インデックスに要素を設定
+    pub fn set(&self, index: Box<dyn NyashBox>, value: Box<dyn NyashBox>) -> Box<dyn NyashBox> {
+        if let Some(idx_box) = index.as_any().downcast_ref::<IntegerBox>() {
+            let idx = idx_box.value as usize;
+            let mut items = self.items.lock().unwrap();
+            if idx < items.len() {
+                items[idx] = value;
+                Box::new(StringBox::new("ok"))
+            } else {
+                Box::new(StringBox::new("Error: index out of bounds"))
+            }
+        } else {
+            Box::new(StringBox::new("Error: set() requires integer index"))
+        }
+    }
+    
+    /// 指定インデックスの要素を削除
+    pub fn remove(&self, index: Box<dyn NyashBox>) -> Box<dyn NyashBox> {
+        if let Some(idx_box) = index.as_any().downcast_ref::<IntegerBox>() {
+            let idx = idx_box.value as usize;
+            let mut items = self.items.lock().unwrap();
+            if idx < items.len() {
+                items.remove(idx)
+            } else {
+                Box::new(NullBox::new())
+            }
+        } else {
+            Box::new(StringBox::new("Error: remove() requires integer index"))
+        }
+    }
+    
+    /// 要素のインデックスを検索
+    pub fn indexOf(&self, item: Box<dyn NyashBox>) -> Box<dyn NyashBox> {
+        let items = self.items.lock().unwrap();
+        for (i, element) in items.iter().enumerate() {
+            if element.equals(item.as_ref()).value {
+                return Box::new(IntegerBox::new(i as i64));
+            }
+        }
+        Box::new(IntegerBox::new(-1))
+    }
+    
+    /// 要素が含まれているか確認
+    pub fn contains(&self, item: Box<dyn NyashBox>) -> Box<dyn NyashBox> {
+        let items = self.items.lock().unwrap();
+        for element in items.iter() {
+            if element.equals(item.as_ref()).value {
+                return Box::new(BoolBox::new(true));
+            }
+        }
+        Box::new(BoolBox::new(false))
+    }
+    
+    /// すべての要素を削除
+    pub fn clear(&self) -> Box<dyn NyashBox> {
+        self.items.lock().unwrap().clear();
+        Box::new(StringBox::new("ok"))
+    }
+    
+    /// 文字列として結合
+    pub fn join(&self, separator: Box<dyn NyashBox>) -> Box<dyn NyashBox> {
+        if let Some(sep_box) = separator.as_any().downcast_ref::<StringBox>() {
+            let items = self.items.lock().unwrap();
+            let parts: Vec<String> = items
+                .iter()
+                .map(|item| item.to_string_box().value)
+                .collect();
+            Box::new(StringBox::new(parts.join(&sep_box.value)))
+        } else {
+            Box::new(StringBox::new("Error: join() requires string separator"))
         }
     }
 }
+
+impl NyashBox for ArrayBox {
+    fn type_name(&self) -> &'static str {
+        "ArrayBox"
+    }
+    
+    fn to_string_box(&self) -> StringBox {
+        let items = self.items.lock().unwrap();
+        let elements: Vec<String> = items
+            .iter()
+            .map(|item| item.to_string_box().value)
+            .collect();
+        StringBox::new(format!("[{}]", elements.join(", ")))
+    }
+    
+    fn clone_box(&self) -> Box<dyn NyashBox> {
+        Box::new(self.clone())
+    }
+    
+    fn equals(&self, other: &dyn NyashBox) -> BoolBox {
+        if let Some(other_array) = other.as_any().downcast_ref::<ArrayBox>() {
+            let self_items = self.items.lock().unwrap();
+            let other_items = other_array.items.lock().unwrap();
+            
+            if self_items.len() != other_items.len() {
+                return BoolBox::new(false);
+            }
+            
+            for (a, b) in self_items.iter().zip(other_items.iter()) {
+                if !a.equals(&**b).value {
+                    return BoolBox::new(false);
+                }
+            }
+            
+            BoolBox::new(true)
+        } else {
+            BoolBox::new(false)
+        }
+    }
+    
+    fn as_any(&self) -> &dyn Any {
+        self
+    }
+    
+    fn box_id(&self) -> u64 {
+        self.id
+    }
+}
+
+impl Display for ArrayBox {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let items = self.items.lock().unwrap();
+        let elements: Vec<String> = items
+            .iter()
+            .map(|item| item.to_string_box().value)
+            .collect();
+        write!(f, "[{}]", elements.join(", "))
+    }
+}
diff --git a/src/boxes/map_box.rs b/src/boxes/map_box.rs
index 088adf55..1770173b 100644
--- a/src/boxes/map_box.rs
+++ b/src/boxes/map_box.rs
@@ -103,7 +103,8 @@
  * - 存在しないキーの取得は "Key not found" メッセージ返却
  */
 
-use crate::box_trait::{NyashBox, StringBox, IntegerBox, BoolBox, ArrayBox};
+use crate::box_trait::{NyashBox, StringBox, IntegerBox, BoolBox};
+use crate::boxes::array::ArrayBox;
 use std::fmt::{Debug, Display};
 use std::any::Any;
 use std::collections::HashMap;
diff --git a/src/boxes/mod.rs b/src/boxes/mod.rs
index 01920945..e29af3b2 100644
--- a/src/boxes/mod.rs
+++ b/src/boxes/mod.rs
@@ -99,9 +99,9 @@ pub mod null_box;
 // pub mod intent_box_wrapper;
 // pub mod p2p_box;
 
-// 今後追加予定のBox型（コメントアウト）
-// pub mod array_box;
-// pub use array_box::ArrayBox;
+// 配列・リスト操作Box
+pub mod array;
+pub use array::ArrayBox;
 
 // null関数も再エクスポート
 pub use null_box::{NullBox, null};
diff --git a/src/interpreter/expressions.rs b/src/interpreter/expressions.rs
index b05d8f6c..f36be539 100644
--- a/src/interpreter/expressions.rs
+++ b/src/interpreter/expressions.rs
@@ -8,6 +8,7 @@
 
 use super::*;
 use crate::ast::UnaryOperator;
+use crate::boxes::array::ArrayBox;
 // TODO: Fix NullBox import issue later
 // use crate::NullBox;
 
@@ -326,6 +327,8 @@ impl NyashInterpreter {
             return self.execute_array_method(array_box, method, arguments);
         }
         
+        // TODO: 以下のBoxはまだ実装されていない
+        /*
         // FileBox method calls
         if let Some(file_box) = obj_value.as_any().downcast_ref::<FileBox>() {
             return self.execute_file_method(file_box, method, arguments);
@@ -345,6 +348,7 @@ impl NyashInterpreter {
         if let Some(channel_box) = obj_value.as_any().downcast_ref::<ChannelBox>() {
             return self.execute_channel_method(channel_box, method, arguments);
         }
+        */
         
         // MathBox method calls
         if let Some(math_box) = obj_value.as_any().downcast_ref::<MathBox>() {
diff --git a/src/interpreter/methods/collection_methods.rs b/src/interpreter/methods/collection_methods.rs
index ef784407..6544a712 100644
--- a/src/interpreter/methods/collection_methods.rs
+++ b/src/interpreter/methods/collection_methods.rs
@@ -8,7 +8,8 @@
  */
 
 use super::super::*;
-use crate::box_trait::{StringBox, IntegerBox, ArrayBox, NyashBox, VoidBox, BoolBox};
+use crate::box_trait::{StringBox, IntegerBox, NyashBox, BoolBox};
+use crate::boxes::array::ArrayBox;
 use crate::boxes::map_box::MapBox;
 
 impl NyashInterpreter {
@@ -48,17 +49,7 @@ impl NyashInterpreter {
                     });
                 }
                 let index_value = self.execute_expression(&arguments[0])?;
-                if let Some(index_int) = index_value.as_any().downcast_ref::<IntegerBox>() {
-                    if let Some(element) = array_box.get(index_int.value as usize) {
-                        Ok(element)
-                    } else {
-                        Ok(Box::new(StringBox::new("Index out of bounds")))
-                    }
-                } else {
-                    Err(RuntimeError::TypeError {
-                        message: "get() requires integer index".to_string(),
-                    })
-                }
+                Ok(array_box.get(index_value))
             }
             "set" => {
                 if arguments.len() != 2 {
@@ -68,18 +59,43 @@ impl NyashInterpreter {
                 }
                 let index_value = self.execute_expression(&arguments[0])?;
                 let element_value = self.execute_expression(&arguments[1])?;
-                if let Some(index_int) = index_value.as_any().downcast_ref::<IntegerBox>() {
-                    match array_box.set(index_int.value as usize, element_value) {
-                        Ok(()) => Ok(Box::new(VoidBox::new())),
-                        Err(msg) => Ok(Box::new(StringBox::new(&msg))),
-                    }
-                } else {
-                    Err(RuntimeError::TypeError {
-                        message: "set() requires integer index".to_string(),
-                    })
-                }
+                Ok(array_box.set(index_value, element_value))
+            }
+            "remove" => {
+                if arguments.len() != 1 {
+                    return Err(RuntimeError::InvalidOperation {
+                        message: format!("remove() expects 1 argument, got {}", arguments.len()),
+                    });
+                }
+                let index_value = self.execute_expression(&arguments[0])?;
+                Ok(array_box.remove(index_value))
+            }
+            "indexOf" => {
+                if arguments.len() != 1 {
+                    return Err(RuntimeError::InvalidOperation {
+                        message: format!("indexOf() expects 1 argument, got {}", arguments.len()),
+                    });
+                }
+                let element = self.execute_expression(&arguments[0])?;
+                Ok(array_box.indexOf(element))
+            }
+            "contains" => {
+                if arguments.len() != 1 {
+                    return Err(RuntimeError::InvalidOperation {
+                        message: format!("contains() expects 1 argument, got {}", arguments.len()),
+                    });
+                }
+                let element = self.execute_expression(&arguments[0])?;
+                Ok(array_box.contains(element))
+            }
+            "clear" => {
+                if !arguments.is_empty() {
+                    return Err(RuntimeError::InvalidOperation {
+                        message: format!("clear() expects 0 arguments, got {}", arguments.len()),
+                    });
+                }
+                Ok(array_box.clear())
             }
-            // Note: indexOf, contains, clear, reverse, slice methods not implemented in ArrayBox yet
             "join" => {
                 if arguments.len() != 1 {
                     return Err(RuntimeError::InvalidOperation {
@@ -87,13 +103,7 @@ impl NyashInterpreter {
                     });
                 }
                 let delimiter_value = self.execute_expression(&arguments[0])?;
-                if let Some(delimiter_str) = delimiter_value.as_any().downcast_ref::<StringBox>() {
-                    Ok(array_box.join(&delimiter_str.value))
-                } else {
-                    Err(RuntimeError::TypeError {
-                        message: "join() requires string delimiter".to_string(),
-                    })
-                }
+                Ok(array_box.join(delimiter_value))
             }
             "isEmpty" => {
                 if !arguments.is_empty() {
diff --git a/src/interpreter/objects.rs b/src/interpreter/objects.rs
index a8bd6933..e15b43c4 100644
--- a/src/interpreter/objects.rs
+++ b/src/interpreter/objects.rs
@@ -9,6 +9,7 @@
 use super::*;
 use crate::boxes::null_box::NullBox;
 use crate::boxes::console_box::ConsoleBox;
+use crate::boxes::array::ArrayBox;
 // use crate::boxes::intent_box_wrapper::IntentBoxWrapper;
 use std::sync::Arc;
 
@@ -29,6 +30,8 @@ impl NyashInterpreter {
                 // 🌍 革命的実装：Environment tracking廃止
                 return Ok(array_box);
             }
+            // TODO: 以下のBoxはまだ実装されていない
+            /*
             "FileBox" => {
                 // FileBoxは引数1個（ファイルパス）で作成
                 if arguments.len() != 1 {
@@ -59,6 +62,7 @@ impl NyashInterpreter {
                 // 🌍 革命的実装：Environment tracking廃止
                 return Ok(result_box);
             }
+            */
             "ErrorBox" => {
                 // ErrorBoxは引数2個（エラータイプ、メッセージ）で作成
                 if arguments.len() != 2 {
@@ -619,9 +623,9 @@ impl NyashInterpreter {
         // 基本的なビルトイン型
         let is_builtin = matches!(type_name, 
             "IntegerBox" | "StringBox" | "BoolBox" | "ArrayBox" | "MapBox" | 
-            "FileBox" | "ResultBox" | "FutureBox" | "ChannelBox" | "MathBox" | 
+            "MathBox" | 
             "TimeBox" | "DateTimeBox" | "TimerBox" | "RandomBox" | "SoundBox" | 
-            "DebugBox" | "MethodBox" | "NullBox" | "ConsoleBox" | "FloatBox"
+            "DebugBox" | "MethodBox" | "NullBox" | "ConsoleBox"
         );
         
         // Web専用Box（WASM環境のみ）
diff --git a/test_array_box.nyash b/test_array_box.nyash
new file mode 100644
index 00000000..f88a0450
--- /dev/null
+++ b/test_array_box.nyash
@@ -0,0 +1,74 @@
+// ArrayBox実装テスト
+print("=== ArrayBox実装テスト ===")
+
+// 1. ArrayBoxの作成
+print("\n1. ArrayBoxの作成:")
+local arr
+arr = new ArrayBox()
+print("ArrayBox created: " + arr.toString())
+// print("Type: " + arr.type_name())  // type_nameはArrayBoxのメソッドではない
+print("Initial length: " + arr.length())
+
+// 2. 要素の追加（push）
+print("\n2. 要素の追加:")
+arr.push("Apple")
+arr.push("Banana")
+arr.push("Cherry")
+arr.push(42)
+arr.push(true)
+print("After push: " + arr.toString())
+print("Length: " + arr.length())
+
+// 3. 要素の取得（get）
+print("\n3. 要素の取得:")
+print("arr.get(0) = " + arr.get(0))
+print("arr.get(1) = " + arr.get(1))
+print("arr.get(3) = " + arr.get(3))
+print("arr.get(10) = " + arr.get(10))  // 範囲外
+
+// 4. 要素の削除（pop）
+print("\n4. 要素の削除:")
+local popped
+popped = arr.pop()
+print("Popped: " + popped)
+print("After pop: " + arr.toString())
+print("Length: " + arr.length())
+
+// 5. インデックス検索（indexOf）
+print("\n5. インデックス検索:")
+print("indexOf('Apple') = " + arr.indexOf("Apple"))
+print("indexOf('Banana') = " + arr.indexOf("Banana"))
+print("indexOf('NotExist') = " + arr.indexOf("NotExist"))
+
+// 6. 要素の確認（contains）
+print("\n6. 要素の確認:")
+print("contains('Apple') = " + arr.contains("Apple"))
+print("contains(42) = " + arr.contains(42))
+print("contains('NotExist') = " + arr.contains("NotExist"))
+
+// 7. 文字列結合（join）
+print("\n7. 文字列結合:")
+print("join(', ') = " + arr.join(", "))
+print("join(' - ') = " + arr.join(" - "))
+
+// 8. 要素の設定（set）
+print("\n8. 要素の設定:")
+arr.set(1, "Orange")
+print("After set(1, 'Orange'): " + arr.toString())
+
+// 9. 要素の削除（remove）
+print("\n9. 要素の削除:")
+local removed
+removed = arr.remove(2)
+print("Removed: " + removed)
+print("After remove(2): " + arr.toString())
+print("Length: " + arr.length())
+
+// 10. 配列のクリア（clear）
+print("\n10. 配列のクリア:")
+arr.clear()
+print("After clear: " + arr.toString())
+print("Length: " + arr.length())
+print("isEmpty: " + arr.isEmpty())
+
+print("\n=== ArrayBoxテスト完了！ ===")
\ No newline at end of file
diff --git a/test_array_simple.nyash b/test_array_simple.nyash
new file mode 100644
index 00000000..c25fecf5
--- /dev/null
+++ b/test_array_simple.nyash
@@ -0,0 +1,23 @@
+// ArrayBox簡単なテスト
+print("=== ArrayBox簡単なテスト ===")
+
+local arr
+arr = new ArrayBox()
+print("Created ArrayBox")
+
+// 要素を追加
+arr.push("Hello")
+arr.push("World")
+print("Added elements")
+
+// 長さを確認
+print("Length: " + arr.length())
+
+// 配列の内容を表示
+print("Array: " + arr.toString())
+
+// 要素を取得
+print("First element: " + arr.get(0))
+print("Second element: " + arr.get(1))
+
+print("\n=== Test complete! ===")
\ No newline at end of file