A method for processing, by a gateway, an X2 message, and a method for transmitting, by a first eNode B (eNB), an X2 message in a wireless communication system are discussed. The method for processing an X2 message according to one embodiment including receiving, by the gateway, an X2 setup request message and target information from a first eNodeB (eNB); transmitting, by the gateway, the received X2 setup request message to a second eNB based on the received target information; receiving, by the gateway, an X2 setup response message from the second eNB; and transmitting, by the gateway, the received X2 setup response message to the first eNB. The target information is additional information of the X2 setup request message. The first eNB is a home eNB (HeNB).