diff --git a/doc/maintainers.rdoc b/doc/maintainers.rdoc
index e5f5b1865e..1a02f5ea80 100644
--- a/doc/maintainers.rdoc
+++ b/doc/maintainers.rdoc
@@ -58,8 +58,6 @@ Zachary Scott (zzak)
   Masatoshi SEKI (seki), Takashi Kokubun (k0kubun)
 [lib/find.rb]
   Kazuki Tsujimoto (ktsj)
-[lib/getoptlong.rb]
-  _unmaintained_
 [lib/mkmf.rb]
   _unmaintained_
 [lib/monitor.rb]
@@ -185,6 +183,10 @@ Zachary Scott (zzak)
   Keiju ISHITSUKA (keiju)
   https://github.com/ruby/forwardable
   https://rubygems.org/gems/forwardable
+[lib/getoptlong.rb]
+  _unmaintained_
+  https://github.com/ruby/getoptlong
+  https://rubygems.org/gems/getoptlong
 [lib/ipaddr.rb]
   Akinori MUSHA (knu)
   https://github.com/ruby/ipaddr
diff --git a/doc/standard_library.rdoc b/doc/standard_library.rdoc
index ca12529846..fc301d6ab4 100644
--- a/doc/standard_library.rdoc
+++ b/doc/standard_library.rdoc
@@ -18,7 +18,6 @@ DRb:: Distributed object system for Ruby
 English.rb:: Require 'English.rb' to reference global variables with less cryptic names
 ERB:: An easy to use but powerful templating system for Ruby
 Find:: This module supports top-down traversal of a set of file paths
-GetoptLong:: Parse command line options similar to the GNU C getopt_long()
 MakeMakefile:: Module used to generate a Makefile for C extensions
 Monitor:: Provides an object or module to use safely by more than one thread
 Net::FTP:: Support for the File Transfer Protocol
@@ -74,6 +73,7 @@ CSV:: Provides an interface to read and write CSV files and data
 E2MM:: Module for defining custom exceptions with specific messages
 FileUtils:: Several file utility methods for copying, moving, removing, etc
 Forwardable:: Provides delegation of specified methods to a designated object
+GetoptLong:: Parse command line options similar to the GNU C getopt_long()
 IPAddr:: Provides methods to manipulate IPv4 and IPv6 IP addresses
 IRB:: Interactive Ruby command-line tool for REPL (Read Eval Print Loop)
 Logger:: Provides a simple logging utility for outputting messages
diff --git a/lib/getoptlong/getoptlong.gemspec b/lib/getoptlong/getoptlong.gemspec
new file mode 100644
index 0000000000..198bba83ac
--- /dev/null
+++ b/lib/getoptlong/getoptlong.gemspec
@@ -0,0 +1,29 @@
+begin
+  require_relative "lib/getoptlong/version"
+rescue LoadError # Fallback to load version file in ruby core repository
+  require_relative "version"
+end
+
+Gem::Specification.new do |spec|
+  spec.name          = "getoptlong"
+  spec.version       = GetoptLong::VERSION
+  spec.authors       = ["Yukihiro Matsumoto"]
+  spec.email         = ["matz@ruby-lang.org"]
+
+  spec.summary       = %q{GetoptLong for Ruby}
+  spec.description   = spec.summary
+  spec.homepage      = "https://github.com/ruby/getoptlong"
+  spec.license       = "BSD-2-Clause"
+
+  spec.metadata["homepage_uri"] = spec.homepage
+  spec.metadata["source_code_uri"] = spec.homepage
+
+  # Specify which files should be added to the gem when it is released.
+  # The `git ls-files -z` loads the files in the RubyGem that have been added into git.
+  spec.files         = Dir.chdir(File.expand_path('..', __FILE__)) do
+    `git ls-files -z`.split("\x0").reject { |f| f.match(%r{^(test|spec|features)/}) }
+  end
+  spec.bindir        = "exe"
+  spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
+  spec.require_paths = ["lib"]
+end
diff --git a/lib/getoptlong/version.rb b/lib/getoptlong/version.rb
new file mode 100644
index 0000000000..6375fb8ad1
--- /dev/null
+++ b/lib/getoptlong/version.rb
@@ -0,0 +1,3 @@
+class GetoptLong
+  VERSION = "0.1.0"
+end