The present invention relates to a 5G or pre-5G communication system for supporting a higher data transmission rate beyond a 4G communication system such as LTE and, more particularly, to a method and a device for controlling transmission power, the method being performed in a base station of a wireless communication system using multiple antennas. The method for controlling transmission power comprises the step of: transmitting a reference signal at a plurality of vertical angles that differ from each other by means of an antenna arrangement; receiving channel state information, which is related to beamforming of a transmission signal, from a terminal which has received the reference signal and measured a channel state; and transmitting the transmission signal to the terminal by means of transmission power which corresponds to the channel state information.