diff --git a/src/aeros_project/service.py b/src/aeros_project/service.py
index c244b4f..bb64823 100644
--- a/src/aeros_project/service.py
+++ b/src/aeros_project/service.py
@@ -38,6 +38,13 @@ async def import_aro_project(*, db_session: DbSession, aeros_project_in: AerosPr
             status_code=400,
             detail=f"Invalid filename: {str(e)}"
         )
+    
+    # Check if mime type is application/octet-stream 
+    if file.content_type != "application/octet-stream":
+        raise HTTPException(
+            status_code=400,
+            detail="Invalid file type. Allowed: application/octet-stream"
+        )
 
     # Get filename
     filename_without_ext = os.path.splitext(clean_filename)[0]