diff --git a/src/stun/ctrans.c b/src/stun/ctrans.c
index 03a6b78..e164b9d 100644
--- a/src/stun/ctrans.c
+++ b/src/stun/ctrans.c
@@ -295,6 +295,7 @@ int stun_ctrans_request(struct stun_ctrans **ctp, struct stun *stun, int proto,
 				  tcp_close_handler, ct);
 		break;
 
+#ifdef USE_DTLS
 	case STUN_TRANSP_DTLS:
 		if (!sock) {
 			err = EINVAL;
@@ -307,6 +308,7 @@ int stun_ctrans_request(struct stun_ctrans **ctp, struct stun *stun, int proto,
 		ct->txc = 1;
 		err = dtls_send(ct->sock, mb);
 		break;
+#endif
 
 	default:
 		err = EPROTONOSUPPORT;
diff --git a/src/stun/stun.c b/src/stun/stun.c
index 9ec738e..6dfdd97 100644
--- a/src/stun/stun.c
+++ b/src/stun/stun.c
@@ -110,9 +110,11 @@ int stun_send(int proto, void *sock, const struct sa *dst, struct mbuf *mb)
 		err = tcp_send(sock, mb);
 		break;
 
+#ifdef USE_DTLS
 	case STUN_TRANSP_DTLS:
 		err = dtls_send(sock, mb);
 		break;
+#endif
 
 	default:
 		err = EPROTONOSUPPORT;
diff --git a/src/turn/turnc.c b/src/turn/turnc.c
index 41f16fe..9a67394 100644
--- a/src/turn/turnc.c
+++ b/src/turn/turnc.c
@@ -538,9 +538,11 @@ int turnc_send(struct turnc *turnc, const struct sa *dst, struct mbuf *mb)
 		err = tcp_send(turnc->sock, mb);
 		break;
 
+#ifdef USE_DTLS
 	case STUN_TRANSP_DTLS:
 		err = dtls_send(turnc->sock, mb);
 		break;
+#endif
 
 	default:
 		err = EPROTONOSUPPORT;