diff --git a/src/openssl.h b/src/openssl.h
index cc5c40d4..6d75007a 100644
--- a/src/openssl.h
+++ b/src/openssl.h
@@ -39,6 +39,9 @@
  * OF SUCH DAMAGE.
  */
 
+/* disable deprecated warnings in OpenSSL 3 */
+#define OPENSSL_SUPPRESS_DEPRECATED
+
 #ifdef LIBSSH2_WOLFSSL
 
 #include <wolfssl/options.h>