A novel kind of optical fiber Raman amplifier was proposed in this paper.It employed low-power laser diode as pumping sources.A genetic algorithm was combined with the simulated annealing method to optimize the configuration of the pump wavelengths as well as pump powers.The optimization speed has been greatly accelerated in comparison with conventional methods.It can also avoid the results from being trapped in the local optimal points.Simulation results show that such a kind of Raman amplifier provides a gain profile of small in-band ripple and sharp out-of-band roll-off.Sharp roll-off feature can save the total pump power.