A weld current generating apparatus includes a voltage conversion circuit, a control circuit, a switch circuit, and a current output circuit. The voltage conversion circuit receives an AC voltage from an AC voltage input terminal, and converts the AC voltage to a DC voltage. The control circuit receives the DC voltage, wherein the control circuit is capable of setting a weld time, and outputting a control signal for controlling the weld time. The switch circuit receives the control signal, and turns on for the weld time according to the control signal. The current output circuit outputs a continuous weld current when the switch circuit turns on.