The invention relates to a direct current deicing apparatus based on an MMC topological structure. The direct current deicing apparatus comprises two-stage three-phase bridge type convertor units; a power module valve group is connected with the upper bridge arm and the lower bridge arm in each phase of the three-phase bridge type convertor units in series; the alternating current side of each stage of the three-phase bridge type convertor units is connected with a transformer; a series switch is connected between the direct current side negative electrode of the first stage of the three-phasebridge type convertor units and the direct current side positive electrode of the second stage of the three-phase bridge type convertor units in series; a positive electrode parallel switch is connected between the positive electrodes of the two-stage three-phase bridge type convertor units in series; and a negative electrode parallel switch is connected between the negative electrodes of the two-stage three-phase bridge type convertor units in series. According to the two-stage three-phase bridge type convertor units disclosed in the invention, series-parallel connection use is realized through the switches, so that deicing requirement of multiple circuits at multiple voltage levels can be satisfied, and relatively high adaptivity is achieved.