provided are a digital current equalizing device , an analog current equalizing device , a current equalizing method and a system . the digital current equalizing device comprises : an output current sampling amplifying module , a digital processing module , and a main power frequency conversion module . an input terminal of the output current sampling amplifying module connects to an output loop of a power supply , and an output terminal of the output current sampling amplifying module connects to a current equalizing bus through a resistor r 0 , wherein the digital processing module is configured to adjust an output voltage reference signal vr according to a difference between an output voltage signal v 2 of the output current sampling amplifying module and an voltage signal vbus of the current equalizing bus , and the main power frequency conversion module is controlled to adjust the voltage according to the adjusted output voltage reference signal vr ′. the technical solution is easy to implement and can improve the reliabilities of each power supply module and the whole power supply system .