Synchronization of a new chaotic system called Liu chaotic system is studied.Based on Lyapunov stabilization theorem and nonlinear feedback control method,the sufficient conditions and range of the controller's parameter for self_synchronization of Liu chaotic systems are derived.By combining the parameter adaptive control method and the nonlinear feedback control method,the synchronization of Liu system at speed with unified chaotic systems is implemented.Simulation results validate the proposed synchronization methode.