In view of the traditional charge pump threshold loss and body effect, a high-gain cross-couple charge pump with two phase non-overlapping clock was proposed, which was not affected by the threshold voltage drop and body effect. On-resistance of each switch was also reduced to improve the gain and the power efficiency. The charge pump was designed and simulated in SMIC standard 0.18 μm CMOS process. The simulation results showed that the proposed charge pump could operate with a supply voltage down to 0.9 V and deliver a maximum output current of about 120 μA. It achieved a voltage gain of 4.8 and a power efficiency of 70.18%.