An apparatus and a method for transmitting/receiving a Physical Uplink Shared CHannel (PUSCH) signal in a cellular radio communication system supporting a Carrier Aggregation (CA) scheme are provided. In the PUSCH transmission method, a User Equipment (UE) transmits a PUSCH signal to a Base Station (BS) based on an UpLink (UL)/DownLink (DL) Configuration, wherein, for a Time Division Duplexing (TDD) scheme, if the UE is configured with more than one serving cell, UL/DL Configurations of at least two serving cells are different, and a serving cell is one of a primary cell and a secondary cell, a UL/DL Configuration for the serving cell is set as a UL-reference UL/DL Configuration based on a pair formed by a UL/DL Configuration for another serving cell and the UL/DL Configuration for the serving cell.