diff --git a/components/net/at/include/at.h b/components/net/at/include/at.h
index b1b80013f832d9f8acc41d678db79eaf478c8b5c..d0040f86cfd09dd34ffc212c47b804df7aa04f37 100644
--- a/components/net/at/include/at.h
+++ b/components/net/at/include/at.h
@@ -251,9 +251,4 @@ void at_port_reset(void);
 void at_port_factory_reset(void);
 #endif
 
-#ifdef AT_USING_CLIENT
-/* AT client port initialization */
-int at_client_port_init(void);
-#endif
-
 #endif /* __AT_H__ */