diff --git a/Gemfile b/Gemfile
index bc12412..1fd08c0 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,4 +8,5 @@ group :development, :test do
   gem "rake"
   gem "pry"
   gem "rspec-rails", "~> 2.0"
+  gem "factory_girl_rails"
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index bf1bc1c..a56132c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -61,6 +61,11 @@ GEM
       unf (>= 0.0.5, < 1.0.0)
     erubis (2.7.0)
     execjs (2.0.2)
+    factory_girl (4.4.0)
+      activesupport (>= 3.0.0)
+    factory_girl_rails (4.4.1)
+      factory_girl (~> 4.4.0)
+      railties (>= 3.0.0)
     fluentd (0.10.46)
       cool.io (>= 1.1.1, < 2.0.0, != 1.2.0)
       http_parser.rb (>= 0.5.1, < 0.7.0)
@@ -188,6 +193,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  factory_girl_rails
   fluentd-ui!
   pry
   rake
diff --git a/app/models/user.rb b/app/models/user.rb
index f573c0d..70c745a 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -1,6 +1,9 @@
 class User < ActiveRecord::Base
   has_secure_password
 
+  validates :name, uniqueness: true, presence: true
+  validates :remember_token, uniqueness: true, allow_nil: true
+
   def generate_remember_token
     begin
       token = SecureRandom.base64(32)
diff --git a/spec/factories/user.rb b/spec/factories/user.rb
new file mode 100644
index 0000000..a61564b
--- /dev/null
+++ b/spec/factories/user.rb
@@ -0,0 +1,7 @@
+FactoryGirl.define do
+  factory :user do
+    sequence(:name) {|n| "user#{n}" }
+    password "passw0rd"
+    password_confirmation "passw0rd"
+  end
+end
diff --git a/spec/models/user_spec.rb b/spec/models/user_spec.rb
index 44032b4..b16884b 100644
--- a/spec/models/user_spec.rb
+++ b/spec/models/user_spec.rb
@@ -1,5 +1,56 @@
 require 'spec_helper'
 
 describe User do
-  pending "add some examples to (or delete) #{__FILE__}"
+  let(:user) { FactoryGirl.build(:user) }
+
+  describe "#generate_remember_token" do
+    subject { user.generate_remember_token }
+    it { User.find_by(remember_token: subject).should be_nil }
+  end
+
+  describe "#valid?" do
+    it { user.should be_valid }
+
+    describe "name" do
+      it "nil is invalid" do
+        user.name = nil
+        user.should_not be_valid
+      end
+
+      it "taken name is invalid" do
+        another_user = FactoryGirl.create(:user)
+        user.name = another_user.name
+        user.should_not be_valid
+      end
+    end
+
+    describe "password" do
+      it "password != password_confirmation is invalid" do
+        user.password = "a"
+        user.password_confirmation = "b"
+        user.should_not be_valid
+      end
+    end
+
+    describe "remember_token" do
+      let(:token) { "xxx" }
+
+      it "nil is valid" do
+        user.remember_token = nil
+        user.should be_valid
+      end
+
+      it "nil and taken is valid " do
+        FactoryGirl.create(:user, remember_token: nil)
+        user.remember_token = nil
+        user.should be_valid
+      end
+
+      it "taken token is invalid" do
+        FactoryGirl.create(:user, remember_token: token)
+        user.remember_token = token
+        user.should_not be_valid
+      end
+    end
+  end
 end