diff --git a/app/Http/Requests/ItemMaster/IndependentFieldStoreRequest.php b/app/Http/Requests/ItemMaster/IndependentFieldStoreRequest.php
index 05f1959..52acba9 100644
--- a/app/Http/Requests/ItemMaster/IndependentFieldStoreRequest.php
+++ b/app/Http/Requests/ItemMaster/IndependentFieldStoreRequest.php
@@ -16,6 +16,7 @@ public function rules(): array
         return [
             'group_id' => 'nullable|integer',
             'field_name' => 'required|string|max:255',
+            'field_key' => 'nullable|string|max:80|regex:/^[a-zA-Z][a-zA-Z0-9_]*$/',
             'field_type' => 'required|in:textbox,number,dropdown,checkbox,date,textarea',
             'is_required' => 'nullable|boolean',
             'default_value' => 'nullable|string',
@@ -24,6 +25,14 @@ public function rules(): array
             'validation_rules' => 'nullable|array',
             'options' => 'nullable|array',
             'properties' => 'nullable|array',
+            'is_locked' => 'nullable|boolean',
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'field_key.regex' => __('validation.field_key_format'),
         ];
     }
 }
diff --git a/app/Http/Requests/ItemMaster/ItemFieldStoreRequest.php b/app/Http/Requests/ItemMaster/ItemFieldStoreRequest.php
index f728e8e..35cc9c5 100644
--- a/app/Http/Requests/ItemMaster/ItemFieldStoreRequest.php
+++ b/app/Http/Requests/ItemMaster/ItemFieldStoreRequest.php
@@ -16,6 +16,7 @@ public function rules(): array
         return [
             'group_id' => 'nullable|integer|min:1', // 계층번호
             'field_name' => 'required|string|max:255',
+            'field_key' => 'nullable|string|max:80|regex:/^[a-zA-Z][a-zA-Z0-9_]*$/',
             'field_type' => 'required|in:textbox,number,dropdown,checkbox,date,textarea',
             'is_required' => 'nullable|boolean',
             'default_value' => 'nullable|string',
@@ -24,6 +25,14 @@ public function rules(): array
             'validation_rules' => 'nullable|array',
             'options' => 'nullable|array',
             'properties' => 'nullable|array',
+            'is_locked' => 'nullable|boolean',
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'field_key.regex' => __('validation.field_key_format'),
         ];
     }
 }
diff --git a/app/Http/Requests/ItemMaster/ItemFieldUpdateRequest.php b/app/Http/Requests/ItemMaster/ItemFieldUpdateRequest.php
index 6ac3590..fc43671 100644
--- a/app/Http/Requests/ItemMaster/ItemFieldUpdateRequest.php
+++ b/app/Http/Requests/ItemMaster/ItemFieldUpdateRequest.php
@@ -15,6 +15,7 @@ public function rules(): array
     {
         return [
             'field_name' => 'sometimes|string|max:255',
+            'field_key' => 'nullable|string|max:80|regex:/^[a-zA-Z][a-zA-Z0-9_]*$/',
             'field_type' => 'sometimes|in:textbox,number,dropdown,checkbox,date,textarea',
             'is_required' => 'nullable|boolean',
             'default_value' => 'nullable|string',
@@ -23,6 +24,14 @@ public function rules(): array
             'validation_rules' => 'nullable|array',
             'options' => 'nullable|array',
             'properties' => 'nullable|array',
+            'is_locked' => 'nullable|boolean',
+        ];
+    }
+
+    public function messages(): array
+    {
+        return [
+            'field_key.regex' => __('validation.field_key_format'),
         ];
     }
 }
diff --git a/app/Models/ItemMaster/ItemField.php b/app/Models/ItemMaster/ItemField.php
index 682076d..2b6da14 100644
--- a/app/Models/ItemMaster/ItemField.php
+++ b/app/Models/ItemMaster/ItemField.php
@@ -15,6 +15,7 @@ class ItemField extends Model
         'tenant_id',
         'group_id',
         'field_name',
+        'field_key',
         'field_type',
         'order_no',
         'is_required',
@@ -27,6 +28,9 @@ class ItemField extends Model
         'category',
         'description',
         'is_common',
+        'is_locked',
+        'locked_by',
+        'locked_at',
         'created_by',
         'updated_by',
         'deleted_by',
@@ -37,6 +41,7 @@ class ItemField extends Model
         'order_no' => 'integer',
         'is_required' => 'boolean',
         'is_common' => 'boolean',
+        'is_locked' => 'boolean',
         'display_condition' => 'array',
         'validation_rules' => 'array',
         'options' => 'array',
@@ -44,6 +49,7 @@ class ItemField extends Model
         'created_at' => 'datetime',
         'updated_at' => 'datetime',
         'deleted_at' => 'datetime',
+        'locked_at' => 'datetime',
     ];
 
     protected $hidden = [
diff --git a/app/Services/ItemMaster/ItemFieldService.php b/app/Services/ItemMaster/ItemFieldService.php
index b618b94..0b4b997 100644
--- a/app/Services/ItemMaster/ItemFieldService.php
+++ b/app/Services/ItemMaster/ItemFieldService.php
@@ -37,6 +37,7 @@ public function storeIndependent(array $data): ItemField
         $tenantId = $this->tenantId();
         $userId = $this->apiUserId();
 
+        // 1. 필드 생성 (field_key 없이)
         $field = ItemField::create([
             'tenant_id' => $tenantId,
             'group_id' => $data['group_id'] ?? 1,
@@ -53,9 +54,17 @@ public function storeIndependent(array $data): ItemField
             'category' => $data['category'] ?? null,
             'description' => $data['description'] ?? null,
             'is_common' => $data['is_common'] ?? false,
+            'is_locked' => $data['is_locked'] ?? false,
+            'locked_by' => ($data['is_locked'] ?? false) ? $userId : null,
+            'locked_at' => ($data['is_locked'] ?? false) ? now() : null,
             'created_by' => $userId,
         ]);
 
+        // 2. field_key 설정 ({ID}_{field_key} 형식)
+        if (! empty($data['field_key'])) {
+            $field->update(['field_key' => $field->id.'_'.$data['field_key']]);
+        }
+
         return $field;
     }
 
@@ -77,6 +86,7 @@ public function clone(int $id): ItemField
             throw new NotFoundHttpException(__('error.field_not_found'));
         }
 
+        // 1. 복제 생성 (field_key, is_locked 없이)
         $cloned = ItemField::create([
             'tenant_id' => $tenantId,
             'group_id' => $original->group_id,
@@ -93,9 +103,17 @@ public function clone(int $id): ItemField
             'category' => $original->category,
             'description' => $original->description,
             'is_common' => $original->is_common,
+            'is_locked' => false, // 복제본은 잠금 해제 상태
             'created_by' => $userId,
         ]);
 
+        // 2. field_key 복제 ({새ID}_{원본key} 형식)
+        if ($original->field_key) {
+            // 원본 field_key에서 키 부분 추출 (예: "81_itemNum" → "itemNum")
+            $originalKey = preg_replace('/^\d+_/', '', $original->field_key);
+            $cloned->update(['field_key' => $cloned->id.'_'.$originalKey.'_copy']);
+        }
+
         return $cloned;
     }
 
@@ -142,7 +160,7 @@ public function store(int $sectionId, array $data): ItemField
             ->where('child_type', EntityRelationship::TYPE_FIELD)
             ->max('order_no');
 
-        // 필드 생성
+        // 1. 필드 생성
         $field = ItemField::create([
             'tenant_id' => $tenantId,
             'group_id' => $data['group_id'] ?? 1,
@@ -156,10 +174,18 @@ public function store(int $sectionId, array $data): ItemField
             'validation_rules' => $data['validation_rules'] ?? null,
             'options' => $data['options'] ?? null,
             'properties' => $data['properties'] ?? null,
+            'is_locked' => $data['is_locked'] ?? false,
+            'locked_by' => ($data['is_locked'] ?? false) ? $userId : null,
+            'locked_at' => ($data['is_locked'] ?? false) ? now() : null,
             'created_by' => $userId,
         ]);
 
-        // 섹션-필드 관계 생성
+        // 2. field_key 설정 ({ID}_{field_key} 형식)
+        if (! empty($data['field_key'])) {
+            $field->update(['field_key' => $field->id.'_'.$data['field_key']]);
+        }
+
+        // 3. 섹션-필드 관계 생성
         EntityRelationship::link(
             $tenantId,
             EntityRelationship::TYPE_SECTION,
@@ -190,7 +216,8 @@ public function update(int $id, array $data): ItemField
             throw new NotFoundHttpException(__('error.not_found'));
         }
 
-        $field->update([
+        // 기본 필드 업데이트
+        $updateData = [
             'field_name' => $data['field_name'] ?? $field->field_name,
             'field_type' => $data['field_type'] ?? $field->field_type,
             'is_required' => $data['is_required'] ?? $field->is_required,
@@ -204,7 +231,28 @@ public function update(int $id, array $data): ItemField
             'description' => $data['description'] ?? $field->description,
             'is_common' => $data['is_common'] ?? $field->is_common,
             'updated_by' => $userId,
-        ]);
+        ];
+
+        // field_key 변경 시 {ID}_{field_key} 형식 유지
+        if (array_key_exists('field_key', $data)) {
+            $updateData['field_key'] = $data['field_key'] ? $field->id.'_'.$data['field_key'] : null;
+        }
+
+        // is_locked 변경 처리
+        if (array_key_exists('is_locked', $data)) {
+            $updateData['is_locked'] = $data['is_locked'];
+            if ($data['is_locked'] && ! $field->is_locked) {
+                // 새로 잠금 설정
+                $updateData['locked_by'] = $userId;
+                $updateData['locked_at'] = now();
+            } elseif (! $data['is_locked'] && $field->is_locked) {
+                // 잠금 해제
+                $updateData['locked_by'] = null;
+                $updateData['locked_at'] = null;
+            }
+        }
+
+        $field->update($updateData);
 
         return $field;
     }
diff --git a/app/Swagger/v1/ItemMasterApi.php b/app/Swagger/v1/ItemMasterApi.php
index 1cb1d73..a46a753 100644
--- a/app/Swagger/v1/ItemMasterApi.php
+++ b/app/Swagger/v1/ItemMasterApi.php
@@ -70,10 +70,13 @@
  *   @OA\Property(property="tenant_id", type="integer", example=1),
  *   @OA\Property(property="group_id", type="integer", nullable=true, example=1, description="계층번호"),
  *   @OA\Property(property="field_name", type="string", example="제품명"),
+ *   @OA\Property(property="field_key", type="string", nullable=true, example="81_itemNum", description="필드 고유 키 ({ID}_{key} 형식)"),
  *   @OA\Property(property="field_type", type="string", enum={"textbox","number","dropdown","checkbox","date","textarea"}, example="textbox"),
  *   @OA\Property(property="order_no", type="integer", example=0),
  *   @OA\Property(property="is_required", type="boolean", example=true),
- *   @OA\Property(property="is_locked", type="boolean", example=false, description="연결 잠금 여부 (init API 응답 시 포함)"),
+ *   @OA\Property(property="is_locked", type="boolean", example=false, description="엔티티 잠금 여부"),
+ *   @OA\Property(property="locked_by", type="integer", nullable=true, example=null, description="잠금 설정자 ID"),
+ *   @OA\Property(property="locked_at", type="string", nullable=true, example=null, description="잠금 설정 일시"),
  *   @OA\Property(property="default_value", type="string", nullable=true, example=null),
  *   @OA\Property(property="placeholder", type="string", nullable=true, example="제품명을 입력하세요"),
  *   @OA\Property(property="display_condition", type="object", nullable=true, example=null),
@@ -201,6 +204,7 @@
  *
  *   @OA\Property(property="group_id", type="integer", nullable=true, example=1, description="계층번호"),
  *   @OA\Property(property="field_name", type="string", maxLength=255, example="제품명"),
+ *   @OA\Property(property="field_key", type="string", nullable=true, maxLength=80, example="itemNum", description="필드 고유 키 (영문+숫자+언더스코어, 저장 시 {ID}_{key} 형식으로 변환)"),
  *   @OA\Property(property="field_type", type="string", enum={"textbox","number","dropdown","checkbox","date","textarea"}, example="textbox"),
  *   @OA\Property(property="is_required", type="boolean", example=false),
  *   @OA\Property(property="default_value", type="string", nullable=true, example=null),
@@ -208,7 +212,8 @@
  *   @OA\Property(property="display_condition", type="object", nullable=true, example=null),
  *   @OA\Property(property="validation_rules", type="object", nullable=true, example=null),
  *   @OA\Property(property="options", type="object", nullable=true, example=null),
- *   @OA\Property(property="properties", type="object", nullable=true, example=null)
+ *   @OA\Property(property="properties", type="object", nullable=true, example=null),
+ *   @OA\Property(property="is_locked", type="boolean", nullable=true, example=false, description="잠금 여부")
  * )
  *
  * @OA\Schema(
@@ -262,6 +267,7 @@
  *
  *   @OA\Property(property="group_id", type="integer", nullable=true, example=1, description="계층번호"),
  *   @OA\Property(property="field_name", type="string", maxLength=255, example="제품명"),
+ *   @OA\Property(property="field_key", type="string", nullable=true, maxLength=80, example="itemNum", description="필드 고유 키 (영문+숫자+언더스코어, 저장 시 {ID}_{key} 형식으로 변환)"),
  *   @OA\Property(property="field_type", type="string", enum={"textbox","number","dropdown","checkbox","date","textarea"}, example="textbox"),
  *   @OA\Property(property="is_required", type="boolean", example=true),
  *   @OA\Property(property="default_value", type="string", nullable=true, example=null),
@@ -269,7 +275,8 @@
  *   @OA\Property(property="display_condition", type="object", nullable=true, example=null),
  *   @OA\Property(property="validation_rules", type="object", nullable=true, example=null),
  *   @OA\Property(property="options", type="object", nullable=true, example=null),
- *   @OA\Property(property="properties", type="object", nullable=true, example=null)
+ *   @OA\Property(property="properties", type="object", nullable=true, example=null),
+ *   @OA\Property(property="is_locked", type="boolean", nullable=true, example=false, description="잠금 여부")
  * )
  *
  * @OA\Schema(
@@ -277,6 +284,7 @@
  *   type="object",
  *
  *   @OA\Property(property="field_name", type="string", maxLength=255, example="제품명"),
+ *   @OA\Property(property="field_key", type="string", nullable=true, maxLength=80, example="itemNum", description="필드 고유 키 (영문+숫자+언더스코어)"),
  *   @OA\Property(property="field_type", type="string", enum={"textbox","number","dropdown","checkbox","date","textarea"}, example="textbox"),
  *   @OA\Property(property="is_required", type="boolean", example=true),
  *   @OA\Property(property="default_value", type="string", nullable=true, example=null),
@@ -284,7 +292,8 @@
  *   @OA\Property(property="display_condition", type="object", nullable=true, example=null),
  *   @OA\Property(property="validation_rules", type="object", nullable=true, example=null),
  *   @OA\Property(property="options", type="object", nullable=true, example=null),
- *   @OA\Property(property="properties", type="object", nullable=true, example=null)
+ *   @OA\Property(property="properties", type="object", nullable=true, example=null),
+ *   @OA\Property(property="is_locked", type="boolean", nullable=true, example=false, description="잠금 여부")
  * )
  *
  * @OA\Schema(
diff --git a/database/migrations/2025_11_28_171952_add_field_key_and_lock_columns_to_item_fields_table.php b/database/migrations/2025_11_28_171952_add_field_key_and_lock_columns_to_item_fields_table.php
new file mode 100644
index 0000000..dfa5463
--- /dev/null
+++ b/database/migrations/2025_11_28_171952_add_field_key_and_lock_columns_to_item_fields_table.php
@@ -0,0 +1,46 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+/**
+ * item_fields 테이블에 field_key 및 잠금 컬럼 추가
+ *
+ * 변경 내용:
+ * 1. field_key: 필드 고유 식별자 ({ID}_{key} 형식, unique)
+ * 2. is_locked: 엔티티 자체 잠금 여부
+ * 3. locked_by: 잠금 설정자 ID
+ * 4. locked_at: 잠금 설정 일시
+ */
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::table('item_fields', function (Blueprint $table) {
+            $table->string('field_key', 100)->nullable()->after('field_name')->comment('필드 고유 키 ({ID}_{key} 형식)');
+            $table->boolean('is_locked')->default(false)->after('is_common')->comment('잠금 여부');
+            $table->unsignedBigInteger('locked_by')->nullable()->after('is_locked')->comment('잠금 설정자 ID');
+            $table->timestamp('locked_at')->nullable()->after('locked_by')->comment('잠금 설정 일시');
+
+            // 인덱스
+            $table->unique(['tenant_id', 'field_key'], 'uq_item_fields_tenant_field_key');
+            $table->index('is_locked', 'idx_item_fields_is_locked');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('item_fields', function (Blueprint $table) {
+            $table->dropUnique('uq_item_fields_tenant_field_key');
+            $table->dropIndex('idx_item_fields_is_locked');
+            $table->dropColumn(['field_key', 'is_locked', 'locked_by', 'locked_at']);
+        });
+    }
+};