diff --git a/include/net/mqtt.h b/include/net/mqtt.h
index 7e0283c1498..9f234fa85f1 100644
--- a/include/net/mqtt.h
+++ b/include/net/mqtt.h
@@ -338,7 +338,7 @@ struct mqtt_sec_config {
 	/** Peer hostname for ceritificate verification.
 	 *  May be NULL to skip hostname verification.
 	 */
-	char *hostname;
+	const char *hostname;
 };
 
 /** @brief MQTT transport type. */