To improve the efficiency of micro-EDM, we designed a pulse power supply which can actively match pulse parameters for micro-EDM. By using the processing method of equal energy, we conducted the comparison experiments of processing efficiency in different pulse parameters, designed the structure, function and control strategy of this pulse power supply, and carried out a machining experiment. The results show that the highest machining efficiency can be obtained by selecting the appropriate pulse width and pulse interval, making the electrode capacitance charge and discharge for only one time, and the pulse parameter of the pulse power supply can automatically adjust to electrode voltage and capacitance. When machining the micro holes, the power supply has good processing continuity, high processing efficiency and quality, and when used for micro machining, the power supply can obviously improve the processing efficiency and get good processing quality compared to the traditional power supply.