Provided are a method and an apparatus for requesting uplink persistent scheduling in a mobile communication system. A terminal generates a semi-persistent scheduling (SPS) buffer status report (BSR) including a size of data and further including at least one of an SPS transmission point in time and an SPS period after configuring SPS between the terminal and a base station, and requests SPS allocation while transmitting the SPS BSR to the base station. The size of the data indicates a size of data that are to be transmitted per SPS period.