A multi-level medium-voltage inverter that receives three-phase power and outputs a three-phase voltage to a three-phase motor, includes: a plurality of unit power cells connected in series to output a single phase voltage, individual unit power cells each having a phase voltage forming a single level to configure multiple levels; and a module-type phase shift transformer configured to convert the three-phase power and applying the converted power to three unit power cells constituting one level, wherein the module-type phase shift transformer includes a plurality of modules.