diff --git a/samples/network/coap_server/src/coap-server.c b/samples/network/coap_server/src/coap-server.c
index 2685f7df90c..d7d3fe336f2 100644
--- a/samples/network/coap_server/src/coap-server.c
+++ b/samples/network/coap_server/src/coap-server.c
@@ -33,6 +33,7 @@
 
 #include <zephyr.h>
 
+#ifdef CONFIG_NANOKERNEL
 #if defined(CONFIG_TINYDTLS)
 /* DTLS needs bigger stack */
 #define STACKSIZE 2500