The present invention relates to a device-to device (D2D) operation method performed by a terminal in a wireless communication system. The method comprises: separately receiving, from a serving cell, measurement bandwidth information about a frequency not included in information indicative of a measurement object for the purpose of supporting the mobility of the terminal; measuring the frequency not included in the measurement object for the purpose of supporting the mobility on the basis of the measurement bandwidth information; selecting a cell on the frequency; and performing discovery announcement on the cell.