diff --git a/ndn-cpp/encoding/binary-xml-structure-decoder.hpp b/ndn-cpp/encoding/binary-xml-structure-decoder.hpp
index e83dd5b..10ab5b5 100644
--- a/ndn-cpp/encoding/binary-xml-structure-decoder.hpp
+++ b/ndn-cpp/encoding/binary-xml-structure-decoder.hpp
@@ -4,7 +4,7 @@
  */
 
 #ifndef NDN_BINARYXMLSTRUCTUREDECODER_HPP
-#define	NDN_BINARYXMLSTRUCTUREDECODER_HPP
+#define NDN_BINARYXMLSTRUCTUREDECODER_HPP
 
 #include <stdexcept>
 #include "../c/encoding/BinaryXMLStructureDecoder.h"