diff --git a/activesupport/CHANGELOG b/activesupport/CHANGELOG
index 8d15d6622f..3aac59931f 100644
--- a/activesupport/CHANGELOG
+++ b/activesupport/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Multibyte: String#slice supports regexp argument.  #9646 [yob]
+
 * object.duplicable? returns true if object.dup is safe. False for nil, true, false, symbols, and numbers; true otherwise.  #9333 [sur]
 
 * Time, Date and DateTime #advance accept :weeks option.  #9866 [Geoff Buesing]
diff --git a/activesupport/lib/active_support/multibyte/handlers/utf8_handler.rb b/activesupport/lib/active_support/multibyte/handlers/utf8_handler.rb
index e4ef98f1b6..2e7e9fac3f 100644
--- a/activesupport/lib/active_support/multibyte/handlers/utf8_handler.rb
+++ b/activesupport/lib/active_support/multibyte/handlers/utf8_handler.rb
@@ -255,6 +255,8 @@ module ActiveSupport::Multibyte::Handlers #:nodoc:
         elsif args[0].kind_of? Range
           cps = u_unpack(str).slice(*args)
           cps.nil? ? nil : cps.pack('U*')
+        elsif args[0].kind_of? Regexp
+          str.slice(*args)
         elsif args.size == 1 && args[0].kind_of?(Numeric)
           u_unpack(str)[args[0]]
         else
diff --git a/activesupport/test/multibyte_handler_test.rb b/activesupport/test/multibyte_handler_test.rb
index 174d7b790d..77b125641d 100644
--- a/activesupport/test/multibyte_handler_test.rb
+++ b/activesupport/test/multibyte_handler_test.rb
@@ -160,6 +160,11 @@ module UTF8HandlingTest
     assert_equal "d Блå ffi", @handler.slice(@string, 3, 7), "Unicode characters have to be returned"
     assert_equal "A", @handler.slice(@string, 0, 1), "Slicing from an offset should return characters"
     assert_equal " Блå ffi ", @handler.slice(@string, 4..10), "Unicode characters have to be returned"
+    assert_equal "ffi бла", @handler.slice(@string, /ffi бла/u), "Slicing on Regexps should be supported"
+    assert_equal "ffi бла", @handler.slice(@string, /ffi \w\wа/u), "Slicing on Regexps should be supported"
+    assert_equal nil, @handler.slice(@string, /unknown/u), "Slicing on Regexps with no match should return nil"
+    assert_equal "ffi бла", @handler.slice(@string, /(ffi бла)/u,1), "Slicing on Regexps with a match group should be supported"
+    assert_equal nil, @handler.slice(@string, /(ffi)/u,2), "Slicing with a Regexp and asking for an invalid match group should return nil"
     assert_equal "", @handler.slice(@string, 7..6), "Range is empty, should return an empty string"
     assert_raise(ActiveSupport::Multibyte::Handlers::EncodingError) { @handler.slice(@bytestring, 2..3) }
     assert_raise(TypeError, "With 2 args, should raise TypeError for non-Numeric or Regexp first argument") { @handler.slice(@string, 2..3, 1) }