A method for setting synchronization between terminals performing device-to-device (D2D) communication based on a cellular communication system is disclosed. The method for setting synchronization between terminals includes receiving a message instructing synchronization setting with an opposite terminal from a base station, selecting a first preamble transmitted for a synchronization setting with the opposite terminal based on the message instructing synchronization setting, transmitting the selected first preamble to the opposite terminal, receiving a second preamble from the opposite terminal, and setting the synchronization with the opposite terminal using a reception timing of the second preamble when the second preamble is a preamble designated in the message instructing synchronization setting. Thus, when the present invention is used, synchronization between two terminals performing direct communication may be set using a physical layer random access channel resource which has been used in an existing mobile communication system.