diff --git a/lib/wukong/script/hadoop_command.rb b/lib/wukong/script/hadoop_command.rb
index 919d0815..e810d117 100644
--- a/lib/wukong/script/hadoop_command.rb
+++ b/lib/wukong/script/hadoop_command.rb
@@ -54,13 +54,17 @@ def jobconf option
     # others
     #
     def execute_hadoop_workflow
+      
+      jar_path = File.join('contrib', 'streaming', 'hadoop-*streaming*.jar')
+      jar_path = File.join('mapred', jar_path) if options[:hadoop_home].include?("0.21.0")
+      
       # Input paths join by ','
       input_paths = @input_paths.join(',')
       #
       # Use Settings[:hadoop_home] to set the path your config install.
       hadoop_commandline = [
-        hadoop_runner,
-        "jar #{options[:hadoop_home]}/contrib/streaming/hadoop-*streaming*.jar",
+        hadoop_runner,        
+        "jar #{File.join(options[:hadoop_home], jar_path)}",
         hadoop_jobconf_options,
         "-D mapred.job.name='#{job_name}'",
         hadoop_other_args,