diff --git a/backend/python/diffusers/backend.py b/backend/python/diffusers/backend.py
index 00b292292949..1b68372d8215 100755
--- a/backend/python/diffusers/backend.py
+++ b/backend/python/diffusers/backend.py
@@ -865,7 +865,12 @@ def GenerateImage(self, request, context):
             ).images[0]
 
         # save the result
-        image.save(request.dst)
+        temp_format = kwargs.get('tmp_file_format')
+        if request.dst.endswith('.tmp') and temp_format:
+            # Enforce uppercase string format (e.g., 'png' -> 'PNG')
+            image.save(request.dst, format=str(temp_format).upper())
+        else:
+            image.save(request.dst)
 
         return backend_pb2.Result(message="Media generated", success=True)
 
diff --git a/docs/content/features/image-generation.md b/docs/content/features/image-generation.md
index fa2a1eb91164..b07eddb214bd 100644
--- a/docs/content/features/image-generation.md
+++ b/docs/content/features/image-generation.md
@@ -212,6 +212,7 @@ The following parameters are available in the configuration file:
 | `pipeline_type` | Pipeline type | `AutoPipelineForText2Image` |
 | `lora_adapters` | A list of lora adapters (file names relative to model directory) to apply | None |
 | `lora_scales` | A list of lora scales (floats) to apply | None |
+| `tmp_file_format` | Specifies the file format used to save temporary output images | None |
 
 
 There are available several types of schedulers: