diff --git a/api/controllers/service_api/dataset/segment.py b/api/controllers/service_api/dataset/segment.py
index e25b08ff8a..19a6700318 100644
--- a/api/controllers/service_api/dataset/segment.py
+++ b/api/controllers/service_api/dataset/segment.py
@@ -14,7 +14,7 @@ from core.model_manager import ModelManager
 from core.model_runtime.entities.model_entities import ModelType
 from extensions.ext_database import db
 from fields.segment_fields import child_chunk_fields, segment_fields
-from models.dataset import ChildChunk, Dataset
+from models.dataset import  Dataset
 from services.dataset_service import DatasetService, DocumentService, SegmentService
 from services.entities.knowledge_entities.knowledge_entities import ChildChunkUpdateArgs, SegmentUpdateArgs
 from services.errors.chunk import (
@@ -336,9 +336,10 @@ class DatasetChildChunkApi(DatasetApiResource):
 
         # check child chunk
         child_chunk_id = str(child_chunk_id)
-        child_chunk = ChildChunk.query.filter(
-            ChildChunk.id == str(child_chunk_id), ChildChunk.tenant_id == current_user.current_tenant_id
-        ).first()
+        child_chunk = SegmentService.get_child_chunk_by_id(
+            child_chunk_id=child_chunk_id,
+            tenant_id=current_user.current_tenant_id
+        )
         if not child_chunk:
             raise NotFound("Child chunk not found.")
 
@@ -376,9 +377,10 @@ class DatasetChildChunkApi(DatasetApiResource):
 
         # check child chunk
         child_chunk_id = str(child_chunk_id)
-        child_chunk = ChildChunk.query.filter(
-            ChildChunk.id == str(child_chunk_id), ChildChunk.tenant_id == current_user.current_tenant_id
-        ).first()
+        child_chunk = SegmentService.get_child_chunk_by_id(
+            child_chunk_id=child_chunk_id,
+            tenant_id=current_user.current_tenant_id
+        )
         if not child_chunk:
             raise NotFound("Child chunk not found.")
 
diff --git a/api/services/dataset_service.py b/api/services/dataset_service.py
index 2a36990e2a..261aedce8a 100644
--- a/api/services/dataset_service.py
+++ b/api/services/dataset_service.py
@@ -2155,6 +2155,14 @@ class SegmentService:
             query = query.where(ChildChunk.content.ilike(f"%{keyword}%"))
         return query.paginate(page=page, per_page=limit, max_per_page=100, error_out=False)
 
+    @classmethod
+    def get_child_chunk_by_id(cls, child_chunk_id: str, tenant_id: str) -> Optional[ChildChunk]:
+        """Get a child chunk by its ID."""
+        return ChildChunk.query.filter(
+            ChildChunk.id == child_chunk_id,
+            ChildChunk.tenant_id == tenant_id
+        ).first()
+
     @classmethod
     def get_segments(
         cls,