diff --git a/network/netssl/include/net_ssl_c_type.h b/network/netssl/include/net_ssl_c_type.h
index fcc9b6fd5..c7096a558 100644
--- a/network/netssl/include/net_ssl_c_type.h
+++ b/network/netssl/include/net_ssl_c_type.h
@@ -38,6 +38,7 @@
  */
 
 #include <stdint.h>
+#include <cstddef>
 
 #ifdef __cplusplus
 extern "C" {