The present invention relates to a method and apparatus in which a base station transmits a physical ARQ channel (PHICH) in a wireless communication system. More particularly, the present invention relates to a method and apparatus for transmitting a PHICH, wherein the method comprises the following steps: generating a plurality of hybrid of ARQ (HARQ) indicators: channel-coding the plurality of HARQ indicators into a single HARQ codeword; and transmitting the HARQ codeword via the PHICH, wherein the value of a portion of the HARQ codeword indicates individual value of each of HARQ indicators, and the value of the rest of the HARQ codeword indicators a value of joint operation of the plurality of HARQ indicators.