The present invention relates to a wireless communication system. More specifically, the present invention relates to a method and a device for disconnecting a device to device (D2D) link connection in a wireless communication system. According to an aspect of the present invention, the method comprising: establishing a radio resource control (RRC) connection with a cell; transmitting, to the cell connected with the remote UE, a reporting message on the D2D link connection; if the cell connected with the remote UE and a cell connected with the relay UE are different, receiving, from the relay UE, a first request message for disconnecting the D2D link connection with the relay UE in response to the reporting message; and disconnecting the D2D link connection according to the first request message.