diff --git a/ChangeLog b/ChangeLog
index 065b0defab..2098b1be65 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Dec 14 18:31:48 2010  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* lib/test/unit.rb: help messages.
+
 Tue Dec 14 18:19:03 2010  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* common.mk (help): there is no reason to use the abbreviation for here.
diff --git a/lib/test/unit.rb b/lib/test/unit.rb
index 2c2085c280..73ce1b82c3 100644
--- a/lib/test/unit.rb
+++ b/lib/test/unit.rb
@@ -79,7 +79,7 @@ module Test
 
       def setup_options(parser, options)
         super
-        parser.on '-x', '--exclude PATTERN' do |pattern|
+        parser.on '-x', '--exclude PATTERN', 'Exclude test files on pattern.' do |pattern|
           (options[:reject] ||= []) << pattern
         end
       end
@@ -117,7 +117,7 @@ module Test
 
       def setup_options(parser, options)
         super
-        parser.on '-Idirectory' do |dirs|
+        parser.on '-Idirectory', 'Add library load path' do |dirs|
           dirs.split(':').each { |d| $LOAD_PATH.unshift d }
         end
       end
@@ -126,7 +126,7 @@ module Test
     module GCStressOption
       def setup_options(parser, options)
         super
-        parser.on '--[no-]gc-stress' do |flag|
+        parser.on '--[no-]gc-stress', 'Set GC.stress as true' do |flag|
           options[:gc_stress] = flag
         end
       end