The invention discloses a global reset circuit, a computer system with the global rest circuit and a global reset method. The global reset circuit is used for the computer system; and the system comprises a mother board, a power supply input device and a control signal generating module. The circuit comprises a first switch module, a second switch module and a capacitor, wherein the power supply input device inputs a power supply signal to the first switch module in order to output a system power supply signal to the mother board; the second switch module is electrically connected with the first switch module; the capacitor is electrically connected with the first and second switch modules; the mother board inputs the system power supply signal to the second switch module, and the control signal generating module inputs a control signal to control the capacitor to be charged; after being charged, the capacitor outputs a high-potential signal to the first switch module to cut off the system power supply signal output by the first switch module; and after the system power supply signal of the second switch module is cut off, the second switch module automatically controls the capacitor to discharge, and outputs a low-potential signal to the first switch module to control the first switch module to restore the output of the system power supply signal. By the invention, the computer system is easily globally reset.