A method and apparatus for transmitting and receiving downlink data for signal combining at a UE in an OFDM cellular system are provided. A Node B sends combining information to the UE, and combinable cells use the same radio resources and the same scrambling sequence in data transmission to the UE. Therefore, the UE can receive naturally combined data without an additional operation. Also, the UE combines channel estimates calculated using pilot signals received form the cells and compensates the combined data signal using the combined channel estimate.