diff --git a/api/.env.example b/api/.env.example
index 562ed970e06245..40f35cff6c66f6 100644
--- a/api/.env.example
+++ b/api/.env.example
@@ -411,4 +411,6 @@ POSITION_PROVIDER_EXCLUDES=
 # Reset password token expiry minutes
 RESET_PASSWORD_TOKEN_EXPIRY_MINUTES=5
 
-CREATE_TIDB_SERVICE_JOB_ENABLED=false
\ No newline at end of file
+CREATE_TIDB_SERVICE_JOB_ENABLED=false
+
+RETRIEVAL_TOP_N=0
\ No newline at end of file
diff --git a/api/configs/feature/__init__.py b/api/configs/feature/__init__.py
index 572f91ad2e7dd9..275b16a9131add 100644
--- a/api/configs/feature/__init__.py
+++ b/api/configs/feature/__init__.py
@@ -626,6 +626,8 @@ class DataSetConfig(BaseSettings):
         default=30,
     )
 
+    RETRIEVAL_TOP_N: int = Field(description="number of retrieval top_n", default=0)
+
 
 class WorkspaceConfig(BaseSettings):
     """
diff --git a/api/core/rag/datasource/retrieval_service.py b/api/core/rag/datasource/retrieval_service.py
index 57af05861c1ad0..759166da4c4be8 100644
--- a/api/core/rag/datasource/retrieval_service.py
+++ b/api/core/rag/datasource/retrieval_service.py
@@ -3,6 +3,7 @@
 
 from flask import Flask, current_app
 
+from configs import DifyConfig
 from core.rag.data_post_processor.data_post_processor import DataPostProcessor
 from core.rag.datasource.keyword.keyword_factory import Keyword
 from core.rag.datasource.vdb.vector_factory import Vector
@@ -110,8 +111,12 @@ def retrieve(
                 str(dataset.tenant_id), reranking_mode, reranking_model, weights, False
             )
             all_documents = data_post_processor.invoke(
-                query=query, documents=all_documents, score_threshold=score_threshold, top_n=top_k
+                query=query,
+                documents=all_documents,
+                score_threshold=score_threshold,
+                top_n=DifyConfig.RETRIEVAL_TOP_N or top_k,
             )
+
         return all_documents
 
     @classmethod
@@ -178,7 +183,10 @@ def embedding_search(
                         )
                         all_documents.extend(
                             data_post_processor.invoke(
-                                query=query, documents=documents, score_threshold=score_threshold, top_n=len(documents)
+                                query=query,
+                                documents=documents,
+                                score_threshold=score_threshold,
+                                top_n=DifyConfig.RETRIEVAL_TOP_N or len(documents),
                             )
                         )
                     else:
@@ -220,7 +228,10 @@ def full_text_index_search(
                         )
                         all_documents.extend(
                             data_post_processor.invoke(
-                                query=query, documents=documents, score_threshold=score_threshold, top_n=len(documents)
+                                query=query,
+                                documents=documents,
+                                score_threshold=score_threshold,
+                                top_n=DifyConfig.RETRIEVAL_TOP_N or len(documents),
                             )
                         )
                     else:
diff --git a/docker/docker-compose.yaml b/docker/docker-compose.yaml
index 3e2b276c92d66e..aa3c810d3faff0 100644
--- a/docker/docker-compose.yaml
+++ b/docker/docker-compose.yaml
@@ -287,6 +287,7 @@ x-shared-env: &shared-api-worker-env
   OCEANBASE_CLUSTER_NAME: ${OCEANBASE_CLUSTER_NAME:-difyai}
   OCEANBASE_MEMORY_LIMIT: ${OCEANBASE_MEMORY_LIMIT:-6G}
   CREATE_TIDB_SERVICE_JOB_ENABLED: ${CREATE_TIDB_SERVICE_JOB_ENABLED:-false}
+  RETRIEVAL_TOP_N: ${RETRIEVAL_TOP_N:-0}
 
 services:
   # API service