diff --git a/bsp/at91sam9260/rtconfig.h b/bsp/at91sam9260/rtconfig.h
index f3caf7f7f2..dadcc3e6b0 100755
--- a/bsp/at91sam9260/rtconfig.h
+++ b/bsp/at91sam9260/rtconfig.h
@@ -163,8 +163,6 @@
 /* Using DHCP */
 /* #define RT_LWIP_DHCP */
 
-#define RT_LWIP_DNS
-
 /* ip address of target */
 #define RT_LWIP_IPADDR0	192
 #define RT_LWIP_IPADDR1	168
diff --git a/bsp/mini2440/rtconfig.h b/bsp/mini2440/rtconfig.h
index d658dd681e..c7fc987a05 100644
--- a/bsp/mini2440/rtconfig.h
+++ b/bsp/mini2440/rtconfig.h
@@ -151,8 +151,6 @@
 /* Using DHCP */
 /* #define RT_LWIP_DHCP */
 
-#define RT_LWIP_DNS
-
 /* ip address of target */
 #define RT_LWIP_IPADDR0	192
 #define RT_LWIP_IPADDR1	168
diff --git a/bsp/mini4020/rtconfig.h b/bsp/mini4020/rtconfig.h
index a92471f16f..b5a0d51945 100644
--- a/bsp/mini4020/rtconfig.h
+++ b/bsp/mini4020/rtconfig.h
@@ -133,8 +133,6 @@
 /* Using DHCP */
 /* #define RT_LWIP_DHCP */
 
-#define RT_LWIP_DNS
-
 /* ip address of target */
 #define RT_LWIP_IPADDR0	192
 #define RT_LWIP_IPADDR1	168