The present invention relates to a wireless communication system supporting device-to-device (D2D) communication. More particularly, a method for allocating transmission resources according to an embodiment of the present invention may comprise: transmitting a first D2D signal in a first resource unit; and when a second D2D signal occurs in a transmission interval of the first resource unit, transmitting the second D2D signal in a second resource unit. Further, the start point of the second resource unit may be set to a specific time point before the end point of the first resource unit.