The invention provides a cross coupling charge pump comprising a boost module and a transmission module; the transmission module comprises a first transmission switch and a second transmission switch; input ends of the first and second transmission switches are respectively connected with a first output end and a second output end of the boost module; output ends of the first and second transmission switches are connected; grid ends of the first and second transmission switches are respectively connected with a first grid voltage control circuit and a second grid voltage control circuit, thus enlarging the grid voltage amplitude of the first and second transmission switches to double the power supply voltage. The cross coupling charge pump uses only two MOSFETs to enlarge the grid voltage amplitude of the PMOS transmission switches, thus using less chip areas; in addition, the substrate voltage of pair transistors can be controlled so as to reduce sub-threshold and conduction dual losses; in addition, the cross coupling charge pump is simple in structure, stable in signals, highly symmetrical in circuit topology, thus effectively reducing influences caused by nonideality factors like circuit mismatch, and providing very good robustness.