diff --git a/tests/unit-tests/security/key.t.cpp b/tests/unit-tests/security/key.t.cpp
new file mode 100644
index 0000000..3d3c4e3
--- /dev/null
+++ b/tests/unit-tests/security/key.t.cpp
@@ -0,0 +1,93 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2015 Regents of the University of California.
+ *
+ * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
+ *
+ * ndn-cxx library is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-cxx library is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+ *
+ * You should have received copies of the GNU General Public License and GNU Lesser
+ * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
+ */
+
+#include "security/key.hpp"
+#include "security/pib.hpp"
+#include "security/in-memory-pib-impl.hpp"
+#include "pib-data-fixture.hpp"
+
+#include "boost-test.hpp"
+
+namespace ndn {
+namespace security {
+namespace tests {
+
+BOOST_AUTO_TEST_SUITE(SecurityKey)
+
+BOOST_FIXTURE_TEST_CASE(ValidityChecking, PibDataFixture)
+{
+  // key
+  Key key;
+
+  BOOST_CHECK_EQUAL(static_cast<bool>(key), false);
+  BOOST_CHECK_EQUAL(!key, true);
+
+  if (key)
+    BOOST_CHECK(false);
+  else
+    BOOST_CHECK(true);
+
+  auto pibImpl = make_shared<InMemoryPibImpl>();
+  key = Key(id1, id1Key1Name.get(-1), id1Key1, pibImpl);
+
+  BOOST_CHECK_EQUAL(static_cast<bool>(key), true);
+  BOOST_CHECK_EQUAL(!key, false);
+
+  if (key)
+    BOOST_CHECK(true);
+  else
+    BOOST_CHECK(false);
+}
+
+BOOST_FIXTURE_TEST_CASE(TestCertificateOperation, PibDataFixture)
+{
+  auto pibImpl = make_shared<InMemoryPibImpl>();
+
+  Key key11(id1, id1Key1Name.get(-1), id1Key1, pibImpl);
+
+  BOOST_CHECK_THROW(key11.getCertificate(id1Key1Cert1.getName()), Pib::Error);
+  key11.addCertificate(id1Key1Cert1);
+  BOOST_CHECK_NO_THROW(key11.getCertificate(id1Key1Cert1.getName()));
+  key11.removeCertificate(id1Key1Cert1.getName());
+  BOOST_CHECK_THROW(key11.getCertificate(id1Key1Cert1.getName()), Pib::Error);
+
+  BOOST_CHECK_THROW(key11.getDefaultCertificate(), Pib::Error);
+  BOOST_REQUIRE_THROW(key11.setDefaultCertificate(id1Key1Cert1.getName()), Pib::Error);
+  BOOST_REQUIRE_NO_THROW(key11.setDefaultCertificate(id1Key1Cert1));
+  BOOST_REQUIRE_NO_THROW(key11.getDefaultCertificate());
+
+  const IdentityCertificate& defaultCert = key11.getDefaultCertificate();
+  BOOST_CHECK_EQUAL_COLLECTIONS(defaultCert.wireEncode().wire(),
+                                defaultCert.wireEncode().wire() + defaultCert.wireEncode().size(),
+                                id1Key1Cert1.wireEncode().wire(),
+                                id1Key1Cert1.wireEncode().wire() + id1Key1Cert1.wireEncode().size());
+
+  key11.removeCertificate(id1Key1Cert1.getName());
+  BOOST_CHECK_THROW(key11.getCertificate(id1Key1Cert1.getName()), Pib::Error);
+  BOOST_CHECK_THROW(key11.getDefaultCertificate(), Pib::Error);
+}
+
+
+BOOST_AUTO_TEST_SUITE_END()
+
+} // namespace tests
+} // namespace security
+} // namespace ndn