A power conversion device, comprising: an inverter that converts a DC current supplied from a DC power source to an AC current by engaging a plurality of switching elements (3a-3c), which constitute an upper arm, and a plurality of switching elements (3d-3f), which constitute a lower arm, in switching operation; a control unit that includes a signal generation unit that generates a switching signal carrying a command for execution of the switching operation in correspondence to each of the plurality of switching elements (3a-3c) constituting the upper arm and the plurality of switching elements (3d-3f) constituting the lower arm, and outputs the switching signal thus generated as a control signal; and a drive unit that individually drives each of the switching elements (3a-3f) based upon the corresponding control signals, wherein the control unit includes a plurality of protection circuits disposed in series on a control signal line extending between the signal generation unit and the drive unit , with each of the protection circuits outputting the control signal having been input thereto when a protective operation is not executed but outputting a control signal for setting the corresponding switching element (3a-3f) either in a cut-off state or in an electrically continuous state in place of the control signal input thereto when the protective operation is executed; characterized in that , the protection circuits include a first protection circuit and a second protection circuit connected to a downstream side of the first protection circuit in series; and the protective operation of the second protection circuit is executed in priority to the protective operation of the first protection circuit. an inverter that converts a DC current supplied from a DC power source to an AC current by engaging a plurality of switching elements (3a-3c), which constitute an upper arm, and a plurality of switching elements (3d-3f), which constitute a lower arm, in switching operation; a control unit that includes a signal generation unit that generates a switching signal carrying a command for execution of the switching operation in correspondence to each of the plurality of switching elements (3a-3c) constituting the upper arm and the plurality of switching elements (3d-3f) constituting the lower arm, and outputs the switching signal thus generated as a control signal; and a drive unit that individually drives each of the switching elements (3a-3f) based upon the corresponding control signals, wherein the control unit includes a plurality of protection circuits disposed in series on a control signal line extending between the signal generation unit and the drive unit , with each of the protection circuits outputting the control signal having been input thereto when a protective operation is not executed but outputting a control signal for setting the corresponding switching element (3a-3f) either in a cut-off state or in an electrically continuous state in place of the control signal input thereto when the protective operation is executed; characterized in that , the protection circuits include a first protection circuit and a second protection circuit connected to a downstream side of the first protection circuit in series; and the protective operation of the second protection circuit is executed in priority to the protective operation of the first protection circuit. <EOS>