An image forming device includes: a processing unit that performs an image forming process on a sheet; a housing that defines a housing space in which the processing unit is housed; a high-voltage board that generates a high voltage to be supplied to the processing unit; a wire that electrically connects the high-voltage board and the processing unit with each other; and a wire holding plate that holds the wire. The housing includes a pair of a first sheet-metal frame and a second sheet-metal frame which oppose each other and a sheet-metal coupling piece which couples these sheet-metal frames, and the first sheet-metal frame and the second sheet-metal frame support the processing unit between the first sheet-metal frame and the second sheet-metal frame. The wire holding plate extends over substantially the entire dimension of the coupling piece in an extending direction thereof and is fixed to the coupling piece.