diff --git a/ChangeLog b/ChangeLog
index cb83017b0e..31e74d39e5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Dec 23 22:04:38 2014  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* lib/uri/generic.rb (URI::Generic#query=): don't escape [\]^
+	  on both rfc2396 and rfc3986. [Bug #10619]
+
 Tue Dec 23 16:03:35 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ext/win32/lib/win32/registry.rb (Win32::Registry::Error#initialize):
diff --git a/lib/uri/generic.rb b/lib/uri/generic.rb
index c0b94a84fe..bacd90382d 100644
--- a/lib/uri/generic.rb
+++ b/lib/uri/generic.rb
@@ -851,7 +851,7 @@ module URI
       v.encode!(Encoding::UTF_8) rescue nil
       v.delete!("\t\r\n")
       v.force_encoding(Encoding::ASCII_8BIT)
-      v.gsub!(/(?!%\h\h|[!$-&(-;=?-Z_a-~])./n.freeze){'%%%02X'.freeze % $&.ord}
+      v.gsub!(/(?!%\h\h|[!$-&(-;=?-_a-~])./n.freeze){'%%%02X'.freeze % $&.ord}
       v.force_encoding(Encoding::US_ASCII)
       @query = v
     end
diff --git a/test/uri/test_generic.rb b/test/uri/test_generic.rb
index 9de40a0276..37605d5de5 100644
--- a/test/uri/test_generic.rb
+++ b/test/uri/test_generic.rb
@@ -714,9 +714,9 @@ class URI::TestGeneric < Test::Unit::TestCase
     assert_equal('b123', uri.fragment = 'b123')
     assert_equal('http://foo:bar@zab:8080/?a=1#b123', uri.to_s)
     assert_equal('a[]=1', uri.query = 'a[]=1')
-    assert_equal('http://foo:bar@zab:8080/?a%5B%5D=1#b123', uri.to_s)
+    assert_equal('http://foo:bar@zab:8080/?a[]=1#b123', uri.to_s)
     uri = URI.parse('http://foo:bar@zab:8080/?a[]=1#b123')
-    assert_equal('http://foo:bar@zab:8080/?a%5B%5D=1#b123', uri.to_s)
+    assert_equal('http://foo:bar@zab:8080/?a[]=1#b123', uri.to_s)
 
     uri = URI.parse('http://example.com')
     assert_raise(URI::InvalidURIError) { uri.password = 'bar' }