diff --git a/src/shrpx.cc b/src/shrpx.cc
index a619fe77..f9fc4739 100644
--- a/src/shrpx.cc
+++ b/src/shrpx.cc
@@ -71,6 +71,7 @@
 
 #include <openssl/ssl.h>
 #include <openssl/err.h>
+#include <openssl/rand.h>
 #include <ev.h>
 
 #include <nghttp2/nghttp2.h>
diff --git a/src/shrpx_quic_connection_handler.cc b/src/shrpx_quic_connection_handler.cc
index c09a4650..d83f0822 100644
--- a/src/shrpx_quic_connection_handler.cc
+++ b/src/shrpx_quic_connection_handler.cc
@@ -24,6 +24,8 @@
  */
 #include "shrpx_quic_connection_handler.h"
 
+#include <openssl/rand.h>
+
 #include <ngtcp2/ngtcp2.h>
 
 #include "shrpx_worker.h"