diff --git a/spec/http_auth_store_spec.cr b/spec/http_auth_store_spec.cr
new file mode 100644
index 0000000..6f566a4
--- /dev/null
+++ b/spec/http_auth_store_spec.cr
@@ -0,0 +1,13 @@
+require "./spec_helper"
+
+describe "Mechanize AuthStore test" do
+  it "add_auth" do
+    auth_store = Mechanize::HTTP::AuthStore.new
+    url = URI.parse("http://example.com/")
+    user = "kanezoh"
+    password = "password"
+    auth_store.add_auth(url, user, password)
+    auth_store.auth_accounts.size.should eq 1
+    auth_store.auth_accounts[url].should eq({"kanezoh", "password"})
+  end
+end