Disclosed are an apparatus and a method for transmitting/receiving data by acquiring channel information of a terminal receiving data in a communication system providing services to users through beamforming according to a multi-input multi-output (MIMO) scheme, wherein so as to acquire channel information of the terminal for transmitting/receiving data through the beamforming according to the MIMO scheme, a null data packet announcement (NDPA) frame and a null data packet (NDP) frame are transmitted to the terminal, the beamforming frame is received from the terminal as a response of the null data packet announcement frame and the null data packet frame, and the channel information of the terminal included in the beamforming frame and the indication information on which the null data packet frame included in a control information field of the beamforming frame is normally received are checked.