diff --git a/backend/open_webui/routers/retrieval.py b/backend/open_webui/routers/retrieval.py
index a6f7cb32d..46725ea90 100644
--- a/backend/open_webui/routers/retrieval.py
+++ b/backend/open_webui/routers/retrieval.py
@@ -1055,10 +1055,27 @@ async def update_rag_config(
     )
 
     # File upload settings
-    request.app.state.config.FILE_MAX_SIZE = form_data.FILE_MAX_SIZE
-    request.app.state.config.FILE_MAX_COUNT = form_data.FILE_MAX_COUNT
-    request.app.state.config.FILE_IMAGE_COMPRESSION_WIDTH = form_data.FILE_IMAGE_COMPRESSION_WIDTH
-    request.app.state.config.FILE_IMAGE_COMPRESSION_HEIGHT = form_data.FILE_IMAGE_COMPRESSION_HEIGHT
+    request.app.state.config.FILE_MAX_SIZE = (
+        form_data.FILE_MAX_SIZE
+        if form_data.FILE_MAX_SIZE is not None
+        else request.app.state.config.FILE_MAX_SIZE
+    )
+    request.app.state.config.FILE_MAX_COUNT = (
+        form_data.FILE_MAX_COUNT
+        if form_data.FILE_MAX_COUNT is not None
+        else request.app.state.config.FILE_MAX_COUNT
+    )
+    request.app.state.config.FILE_IMAGE_COMPRESSION_WIDTH = (
+        form_data.FILE_IMAGE_COMPRESSION_WIDTH
+        if form_data.FILE_IMAGE_COMPRESSION_WIDTH is not None
+        else request.app.state.config.FILE_IMAGE_COMPRESSION_WIDTH
+    )
+    request.app.state.config.FILE_IMAGE_COMPRESSION_HEIGHT = (
+        form_data.FILE_IMAGE_COMPRESSION_HEIGHT
+        if form_data.FILE_IMAGE_COMPRESSION_HEIGHT is not None
+        else request.app.state.config.FILE_IMAGE_COMPRESSION_HEIGHT
+    )
+
     request.app.state.config.ALLOWED_FILE_EXTENSIONS = (
         form_data.ALLOWED_FILE_EXTENSIONS
         if form_data.ALLOWED_FILE_EXTENSIONS is not None