Abstract: To increase the voltage gain of the DC-DC converter, reduce the voltage stress of the switch, combine the coupled inductor multiplier unit with the diode-capacitor multiplier(DCM) unit, and a double DCM structure is proposed and introduced into a non-isolated converter with output diode. Not only the voltage gain of the converter is improved, but also the voltage stress of the semiconductor is reduced. Meanwhile, the diode-capacitor branch in the structure is used as a passive clamping branch to absorb the leakage inductor energy and improve the efficiency of the converter. The working mode and working performance of the proposed SEPIC-based converter are analyzed, which containing a double DCM structure. The working state of the inductor current is analyzed. Compared with the same type converter, the advantages of proposed type of converter with high gain and low stress are fully proven. Finally, a 60 W experimental prototype is built to verify the correctness of the theory.