diff --git a/activesupport/lib/active_support/gzip.rb b/activesupport/lib/active_support/gzip.rb
index 35a50e9a777f5..fddbfb0ab7f1e 100644
--- a/activesupport/lib/active_support/gzip.rb
+++ b/activesupport/lib/active_support/gzip.rb
@@ -5,6 +5,10 @@ module ActiveSupport
   # A convenient wrapper for the zlib standard library that allows compression/decompression of strings with gzip.
   module Gzip
     class Stream < StringIO
+      def initialize(*)
+         super
+         set_encoding "BINARY" if "".encoding_aware?
+       end
       def close; rewind; end
     end
 
diff --git a/activesupport/test/gzip_test.rb b/activesupport/test/gzip_test.rb
index 2a24c0bd0d046..6adfab0359762 100644
--- a/activesupport/test/gzip_test.rb
+++ b/activesupport/test/gzip_test.rb
@@ -4,4 +4,14 @@ class GzipTest < Test::Unit::TestCase
   def test_compress_should_decompress_to_the_same_value
     assert_equal "Hello World", ActiveSupport::Gzip.decompress(ActiveSupport::Gzip.compress("Hello World"))
   end
+
+  def test_compress_should_return_a_binary_string
+    compressed = ActiveSupport::Gzip.compress('')
+
+    if "".encoding_aware?
+      assert_equal Encoding.find('binary'), compressed.encoding
+    end
+
+    assert !compressed.blank?, "a compressed blank string should not be blank"
+  end
 end
\ No newline at end of file