Abstract: This paper proposes a resource allocation algorithm (ESFC) for multiuser OFDM system, which can allocate the subcarrier, bit and power among users with low complexity and achieve the fast optimization of system transmitting power. By considering the realtime dynamic service and fair competition among users, the resource allocation problem is changed into a multiconstrained optimization problem. The proposed algorithm is composed of two steps, i.e., the allocation of subcarrier based on evolution strategy, and the allocation of bits and power based on waterfilling algorithm. The simulation results show that, compared with the existing algorithms, the present algorithm can attain a better realtime requirement while optimizing the performance of OFDM system. Moreover, it can effectively reduce the amount of computation and quicken the convergence to the optimal solution.