Abstract: Described are a method for suppressing overshoot of an output voltage or output current, a charging device, and a medium. The method for suppressing the overshoot of the output voltage or output current includes the following. A loop in an open-loop state in a closed-loop control circuit is determined. A wave-sending control value output by the closed-loop control circuit at a present beat is obtained. The wave-sending control value output at the present beat is assigned to an open-loop output value at the present beat, where the open-loop output value is an output value of the loop in the open-loop state. An open-loop output value of a loop in the open-loop state at a next beat is calculated by using an assigned open-loop output value at the present beat.