diff --git a/lib/libwebsockets.h b/lib/libwebsockets.h
index b125d1b88..fe052fb0d 100644
--- a/lib/libwebsockets.h
+++ b/lib/libwebsockets.h
@@ -106,7 +106,8 @@ typedef unsigned long long lws_intptr_t;
 #include <sys/capability.h>
 #endif
 
-#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__QNX__)
+#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__QNX__) || defined(__OpenBSD__)
+#include <sys/socket.h>
 #include <netinet/in.h>
 #endif