The present invention discloses an MMC dual sub-module topology with a DC-side fault self-clearing capability. Two half-bridge modules are connected in series by a connecting circuit, the input end ofthe output end of the dual sub-module are connected in parallel with a reverse blocking circuit. The connecting circuit in the dual sub-module is formed by connecting an insulated gate bipolar transistor and a diode in anti-parallel mode; and the reverse blocking circuit is formed by connecting a capacitor and a diode in series. When a fault occurs on the DC side, the reverse blocking circuit hasan effect for clearing a fault current, the dual sub-module has good universality, can be used for hybrid sub-module topology to allow the converter to have a DC fault clearing capability so as to ensure the safe and reliable operation of the MMC-HVDC system.