diff --git a/actionpack/lib/action_dispatch/http/upload.rb b/actionpack/lib/action_dispatch/http/upload.rb
index <HASH>..<HASH> 100644
--- a/actionpack/lib/action_dispatch/http/upload.rb
+++ b/actionpack/lib/action_dispatch/http/upload.rb
@@ -27,7 +27,7 @@ module ActionDispatch
         @tempfile          = hash[:tempfile]
         raise(ArgumentError, ':tempfile is required') unless @tempfile
 
-        @original_filename = encode_filename(hash[:filename])
+        @original_filename = hash[:filename]
         @content_type      = hash[:type]
         @headers           = hash[:head]
       end
@@ -66,13 +66,6 @@ module ActionDispatch
       def eof?
         @tempfile.eof?
       end
-
-      private
-
-      def encode_filename(filename)
-        # Encode the filename in the utf8 encoding, unless it is nil
-        filename.force_encoding(Encoding::UTF_8).encode! if filename
-      end
     end
   end
 end
rack <I> encodes the filenames in posts correctly now