diff --git a/ssh-ecdsa-sk.c b/ssh-ecdsa-sk.c
index 083787952..981d60d74 100644
--- a/ssh-ecdsa-sk.c
+++ b/ssh-ecdsa-sk.c
@@ -31,10 +31,12 @@
 
 #include <sys/types.h>
 
+#ifdef WITH_OPENSSL
 #include <openssl/bn.h>
 #include <openssl/ec.h>
 #include <openssl/ecdsa.h>
 #include <openssl/evp.h>
+#endif
 
 #include <string.h>
 #include <stdio.h> /* needed for DEBUG_SK only */