The present invention relates to a wireless communication system. More particularly, the present invention relates to a method and apparatus for transmitting channel quality information by a terminal in a wireless communication system, the method comprising: receiving information on a plurality of transmission nodes capable of performing CoMP transmission; transmitting first channel state information on one or more preferred transmission nodes from among the plurality of transmission nodes; receiving pattern information consisting of a plurality of combinations of CoMP sets, each of which corresponds to a relevant time interval according to the pattern information; and performing an operation for transmitting second channel state information on the combination of CoMP sets corresponding to a subframe n.