A device-to-device (D2D) communication method is provided. The D2D communication method includes the operations of receiving, by a first terminal, system information including a threshold value for link quality with a base station (BS) from the BS, measuring, by the first terminal, the strength of a signal from a serving cell, comparing, by the first terminal, the measured strength of the signal with the threshold value, and searching for a second terminal acting as a relay between the first terminal and a network when the measured strength of the signal is less than the threshold value on the basis of the compared result.