A system and a method minimize power consumption, signalling overhead, and processing load in blind scheduling in a mobile communication system. A User Equipment (UE) detects a type of an uplink (UL) grant while it is periodically allocated the UL grant. If there is no data to transmit using the UL grant, the UE determines whether to transmit a padding Medium Access Control (MAC) Protocol Data Unit (PDU) to an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (eNB) using the UL grant according to the type of the UL grant.