The aim of this paper is to discuss the dislocated feedback control, enhancing feedback control and speed feedback control for controlling chaos in a unified chaotic system.These control strategies are based on the Luapunov stability theory and Routh-Hurwitz theorem. The sufficient conditions for the control parameter for controlling chaos in the unified chaotic system by using the above three methods are derived. Finally, numerical simulation results are presented to demnonstrate the effectiveness of the control strategies.