The invention discloses a photovoltaic grid-connected inverter space voltage vector double hysteresis current control method and system. The line current is subjected to decoupling control by utilizing the relationship between the line current and the power device on-off state of a photovoltaic grid-connected inverter, the reference space voltage vector position is detected by utilizing the double hysteresis, a PLL (phase locked loop) circuit is combined for detecting the output switching value, and the frequency closed-loop control is formed. The method and the system have the advantages that on the basis of maintaining the advantages of high current response speed, certain current limiting capability and the like of the traditional hysteresis control, the constant on-off frequency of a power device can effectively maintained, the on-off loss of the power device is reduced, the design of a driving circuit and a protecting circuit is favorably realized, and good practical application values are realized.