A control information interpretation method of a terminal and a base station in a mobile communication system, and a terminal and a base station concerning the same, respectively, are provided. The control information interpretation method of a terminal includes receiving, by the terminal, control information including transport block information and antenna port related information; identifying whether a codeword 0 is enabled and a codeword 1 is disabled, or both the codeword 0 and the codeword 1 are enabled based on the transport block information; and interpreting the antenna port related information according to a result of the identification.