diff --git a/src/detail/challenge-encoder.hpp b/src/detail/challenge-encoder.hpp
index fb9d5d2..b47938e 100644
--- a/src/detail/challenge-encoder.hpp
+++ b/src/detail/challenge-encoder.hpp
@@ -21,7 +21,7 @@
 #ifndef NDNCERT_DETAIL_CHALLENGE_STEP_HPP
 #define NDNCERT_DETAIL_CHALLENGE_STEP_HPP
 
-#include "detail/ca-state.hpp"
+#include "detail/ca-request-state.hpp"
 #include "requester-state.hpp"
 
 namespace ndn {