diff --git a/ndn-cpp/key-chain.hpp b/ndn-cpp/key-chain.hpp
index 63863aa..97991e9 100644
--- a/ndn-cpp/key-chain.hpp
+++ b/ndn-cpp/key-chain.hpp
@@ -4,7 +4,7 @@
  */
 
 #ifndef NDN_KEY_CHAIN_HPP
-#define	NDN_KEY_CHAIN_HPP
+#define NDN_KEY_CHAIN_HPP
 
 #include "data.hpp"