A method and an apparatus for transmitting and receiving data in resource reallocation in a wireless communication system are provided. The method includes transmitting control information for the uplink resource reallocation to a corresponding terminal, according to the uplink resource reallocation, receiving an uplink packet from the corresponding terminal and determining whether the corresponding terminal receives the control information, and when the corresponding terminal does not receive the control information, informing the corresponding terminal of the determination result by transmitting a NULL signal over a feedback channel for previous uplink resource allocation. Thus, the resource utilization of the system can be raised by preventing repeated data retransmission until a next resource reallocation period.