The present invention relates to a method and a device for transmitting, by a first terminal, a device-to-device (D2D) signal in a wireless communication system. Particularly, the method comprises the steps of: performing D2D transmission scheduling for a device-to-device synchronization signal (D2DSS) and a device-to-device channel (D2DCH); and transmitting a D2D signal on a first D2D subframe among a plurality of D2D subframes, wherein the first D2D subframe is a D2D subframe in which a D2D synchronization signal transmission for the first terminal is configured among D2D subframes configured to enable a D2D synchronization signal transmission, and the D2D signal drops the D2DCH when the D2DSS and the D2DCH are simultaneously scheduled on the first D2D subframe.