An efficient Cockcroft-Walton type charge pump (CP) is proposed in this paper. In the proposed charge pump, to overcome the reverse current problem, a level shift control circuit is used, which would increase the efficiency. The CP is verified by circuit simulation, using a standard 0.18μm CMOS process. The simulation results indicate that the voltage boosting efficiency of the charge pump is 99.1% when the load current is 1μA while the conventional circuit drops to 96.7%. The power efficiency of the proposed circuit is 85.4% when the load current is 100μA without the stray capacitance.