diff --git core/lib/mikutwitter/test/test_api_call_support.rb core/lib/mikutwitter/test/test_api_call_support.rb
index 1255c22..b0d4856 100644
--- core/lib/mikutwitter/test/test_api_call_support.rb
+++ core/lib/mikutwitter/test/test_api_call_support.rb
@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 require "#{File.dirname(__FILE__)}/extension"
 require 'test/unit'
-require 'mocha'
+require 'mocha/setup'
 require 'webmock/test_unit'
 require 'pp'
 require 'utils'
diff --git core/lib/mikutwitter/test/test_api_shortcuts.rb core/lib/mikutwitter/test/test_api_shortcuts.rb
index dc189d2..64870fa 100644
--- core/lib/mikutwitter/test/test_api_shortcuts.rb
+++ core/lib/mikutwitter/test/test_api_shortcuts.rb
@@ -2,7 +2,7 @@
 require "#{File.dirname(__FILE__)}/extension"
 
 require 'test/unit'
-require 'mocha'
+require 'mocha/setup'
 require 'webmock/test_unit'
 require 'pp'
 require 'utils'
diff --git core/lib/mikutwitter/test/test_cache.rb core/lib/mikutwitter/test/test_cache.rb
index 803a280..48c7d33 100644
--- core/lib/mikutwitter/test/test_cache.rb
+++ core/lib/mikutwitter/test/test_cache.rb
@@ -2,7 +2,7 @@
 require "#{File.dirname(__FILE__)}/extension"
 
 require 'test/unit'
-require 'mocha'
+require 'mocha/setup'
 require 'webmock/test_unit'
 require 'pp'
 require 'utils'
diff --git core/lib/mikutwitter/test/test_query.rb core/lib/mikutwitter/test/test_query.rb
index b8ddf31..e0dccd4 100644
--- core/lib/mikutwitter/test/test_query.rb
+++ core/lib/mikutwitter/test/test_query.rb
@@ -2,7 +2,7 @@
 require "#{File.dirname(__FILE__)}/extension"
 
 require 'test/unit'
-require 'mocha'
+require 'mocha/setup'
 require 'webmock'
 
 require 'utils'
diff --git core/lib/mikutwitter/test/test_streaming_failed_actions.rb core/lib/mikutwitter/test/test_streaming_failed_actions.rb
index 7e79e28..364376e 100644
--- core/lib/mikutwitter/test/test_streaming_failed_actions.rb
+++ core/lib/mikutwitter/test/test_streaming_failed_actions.rb
@@ -2,7 +2,7 @@
 require "#{File.dirname(__FILE__)}/extension"
 
 require 'test/unit'
-require 'mocha'
+require 'mocha/setup'
 require 'webmock'
 
 require 'utils'
diff --git core/lib/mikutwitter/test/test_utils.rb core/lib/mikutwitter/test/test_utils.rb
index 85d2500..a77ebd7 100644
--- core/lib/mikutwitter/test/test_utils.rb
+++ core/lib/mikutwitter/test/test_utils.rb
@@ -2,7 +2,7 @@
 require "#{File.dirname(__FILE__)}/extension"
 
 require 'test/unit'
-require 'mocha'
+require 'mocha/setup'
 require 'webmock'
 require 'mikutwitter/connect'
 require 'test_unit_extensions'
diff --git core/plugin/bitly/test.bitly.rb core/plugin/bitly/test.bitly.rb
index a4c0ccf..1aa2bdc 100644
--- core/plugin/bitly/test.bitly.rb
+++ core/plugin/bitly/test.bitly.rb
@@ -2,7 +2,7 @@
 
 require 'test/unit'
 require 'rubygems'
-require 'mocha'
+require 'mocha/setup'
 require File.expand_path(File.dirname(__FILE__) + '/../../utils')
 miquire :addon, 'bitly'
 
diff --git core/plugin/settings/test_listener.rb core/plugin/settings/test_listener.rb
index c055a60..a5eb65a 100644
--- core/plugin/settings/test_listener.rb
+++ core/plugin/settings/test_listener.rb
@@ -2,7 +2,7 @@
 
 require 'test/unit'
 require 'rubygems'
-require 'mocha'
+require 'mocha/setup'
 require 'pp'
 listener = File.expand_path File.join(File.dirname(__FILE__), 'listener')
 require File.expand_path(File.dirname(__FILE__) + '/../../utils')
diff --git core/plugin/tco/test_tco.rb core/plugin/tco/test_tco.rb
index f6c7b97..657653a 100644
--- core/plugin/tco/test_tco.rb
+++ core/plugin/tco/test_tco.rb
@@ -2,7 +2,7 @@
 
 require 'test/unit'
 require 'rubygems'
-require 'mocha' # !> global variable `$openimg' not initialized
+require 'mocha/setup' # !> global variable `$openimg' not initialized
 require File.expand_path(File.dirname(__FILE__) + '/../../utils') # !> redefine call_routine
 miquire :addon, 'tco'
 
diff --git test/helper.rb test/helper.rb
index 63f4f16..19a457d 100644
--- test/helper.rb
+++ test/helper.rb
@@ -11,7 +11,7 @@ rescue Bundler::BundlerError => e
 end
 
 require 'test/unit'
-require 'mocha'
+require 'mocha/setup'
 
 $LOAD_PATH.unshift(File.join(File.dirname(__FILE__),'..','core'))
 $LOAD_PATH.unshift(File.dirname(__FILE__))