The invention relates to an explosion-proof property testing circuit and method of a damping capacitor for a direct current transmission converter valve, and belongs to the technical field of direct current transmission. Firstly, a direct current power source is exerted on the damping capacitor to be tested, and direct current voltage is modulated until the damping capacitor to be tested breaks down; then alternating current voltage is exerted on the breakdown damping capacitor, and the interior of the breakdown damping capacitor generates a breaking point as a gas explosion-proof structure generated inside under the action of the current is pulled open; finally, whether the breaking point generated by the damping capacitor to be tested can bear the peak value of the exerted alternating current voltage or not is detected, and then testing on the explosion-proof property of the damping capacitor is finished. The testing process is simple, cost of the adopted equipment is low, the current is small, an additional cooling mode does not need to be considered, the equipment cost and operation cost of the whole system are lowered, the parameter adjustment range is wide, control is flexible, and the requirement for the explosion-proof property testing of the damping capacitor for the converter valve of different high-voltage direct current transmission projects can be met.