The present invention is to provide a method and device for controlling transmission power by taking comprehensive consideration not only of the effect received onto itself in each device-to-device (D2D) link of a D2D communication network but also of the effect exerted onto the neighboring links. According to an embodiment of the present invention, a processing method in a transmission terminal of a first link for controlling the transmission power of the transmission terminals of links in a D2D communication network, which includes terminals of at least the first link and terminals of a second link adjacent to the first link includes: measuring the strengths of first detection signals transmitted from reception terminals of the first link and the second link; and determining a first transmission power adjustment ratio for the transmission terminal of the first link so that a signal-to-interference ratio of the second link is greater than or equal to a predetermined threshold value on the basis of the measured strengths of the first detection signals.