The present invention provides a method for resource allocation, a base station and a mobile communication terminal. The method includes: setting a persistent radio resource set and a complementary resource set pre-allocated to a terminal; determining a radio resource to be used according to the size of a packet to be transmitted by the terminal or the base station. According to one embodiment of the present invention, when a whole packet cannot be transmitted by using the pre-allocated persistent resource, the complementary resource can be allocated to the terminal so that the packet doesn't need to be divided, time delay is reduced, physical layer control information is decreased and the number of accommodated terminal users is increased. The present invention is applicable to any service in which packets arrive periodically, such as VoIP service and real-time service.