diff --git a/tools/ndnsec/key-gen.cpp b/tools/ndnsec/key-gen.cpp
new file mode 100644
index 0000000..584b79c
--- /dev/null
+++ b/tools/ndnsec/key-gen.cpp
@@ -0,0 +1,124 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2017 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 "ndnsec.hpp"
+#include "util.hpp"
+
+namespace ndn {
+namespace ndnsec {
+
+int
+ndnsec_key_gen(int argc, char** argv)
+{
+  using namespace ndn;
+  namespace po = boost::program_options;
+
+  std::string identityName;
+  bool isDefault = true;
+  char keyType = 'r';
+  std::string outputFilename;
+
+  po::options_description description("General Usage\n"
+                                      "  ndnsec key-gen [-h] [-n] identity\n"
+                                      "General options");
+  description.add_options()
+    ("help,h", "produce help message")
+    ("identity,i", po::value<std::string>(&identityName),
+     "identity name, for example, /ndn/edu/ucla/alice")
+    ("not_default,n",
+     "optional, if not specified, the target identity will be set as "
+     "the default identity of the system")
+    ("dsk,d", "generate Data-Signing-Key (DSK) instead of the default Key-Signing-Key (KSK)")
+    ("type,t", po::value<char>(&keyType)->default_value('r'),
+    "optional, key type, r for RSA key (default), e for EC key")
+    // ("size,s", po::value<int>(&keySize)->default_value(2048),
+    // "optional, key size, 2048 (default)")
+    ;
+
+  po::positional_options_description p;
+  p.add("identity", 1);
+
+  po::variables_map vm;
+  try {
+    po::store(po::command_line_parser(argc, argv).options(description).positional(p).run(), vm);
+    po::notify(vm);
+  }
+  catch (const std::exception& e) {
+    std::cerr << "ERROR: " << e.what() << std::endl;
+    std::cerr << description << std::endl;
+    return 1;
+  }
+
+  if (vm.count("help") != 0) {
+    std::cerr << description << std::endl;
+    return 0;
+  }
+
+  if (vm.count("identity") == 0) {
+    std::cerr << "identity must be specified" << std::endl;
+    std::cerr << description << std::endl;
+    return 1;
+  }
+
+  if (vm.count("not_default") != 0)
+    isDefault = false;
+
+  bool isKsk = (vm.count("dsk") == 0);
+
+  security::v1::KeyChain keyChain;
+  Name keyName;
+
+  try {
+    switch (keyType) {
+      case 'r':
+        keyName = keyChain.generateRsaKeyPair(Name(identityName), isKsk, RsaKeyParams().getKeySize());
+        break;
+      case 'e':
+        keyName = keyChain.generateEcKeyPair(Name(identityName), isKsk, EcKeyParams().getKeySize());
+        break;
+      default:
+        std::cerr << "Unrecongized key type\n"
+                  << description << std::endl;
+        return 1;
+    }
+
+    if (keyName.empty()) {
+      std::cerr << "Error: failed to generate key" << std::endl;
+      return 1;
+    }
+
+    keyChain.setDefaultKeyNameForIdentity(keyName);
+
+    shared_ptr<security::v1::IdentityCertificate> identityCert = keyChain.selfSign(keyName);
+
+    if (isDefault)
+      keyChain.setDefaultIdentity(Name(identityName));
+
+    io::save(*identityCert, std::cout);
+  }
+  catch (const std::exception& e) {
+    std::cerr << "Error: " << e.what() << std::endl;
+  }
+  return 0;
+}
+
+} // namespace ndnsec
+} // namespace ndn