diff --git a/Gemfile b/Gemfile
index 098a33ee7..97a1c5e56 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,6 +8,6 @@ group :test do
   gem "shoulda"
   gem "rake"
   gem "mocha"
-  gem "nokogiri"
+  gem "nokogiri", ">= 1.5.0"
   gem "timecop"
 end
diff --git a/ruby-saml.gemspec b/ruby-saml.gemspec
index 528114297..484f62ed8 100644
--- a/ruby-saml.gemspec
+++ b/ruby-saml.gemspec
@@ -25,5 +25,5 @@ Gem::Specification.new do |s|
 
   s.add_runtime_dependency("canonix", ["0.1.1"])
   s.add_runtime_dependency("uuid", ["~> 2.3"])
-  s.add_runtime_dependency("nokogiri")
+  s.add_runtime_dependency("nokogiri", [">= 1.5.0"])
 end