In this printing apparatus selectively as a manufacturing apparatus of an image drum manufacturing method using the same, and to adsorb the toner for image formation is started. Method of manufacturing the image drum comprising: providing a core portion formed in a substantially hollow cylindrical shape to the inner surface in the circumferential direction with the radius of the forming die, and smaller than the hollow of the forming mold engraved a plurality of molding grooves having a binding groove of the slit-shaped , filling the conductive material in the molding grooves of the molding mold, inserting to partially expose a control unit for applying voltage independently to each of the terminals to the conductive pattern is outside corresponding to the conductive material in the core portion of the binding groove, challenge a step of a conductive material in the pattern and the molding groove by filling the molten plastic in the space between the corresponding mold on the stage and the mold for inserting the core portion to the core portion to form a drum body forming the control unit and an electrically conductive material and integrally do. And injection molding a conductive material on the surface of the drum body, so formed through the drum body insert injection for receiving the control unit which can be engraved to individually ring electrode in the prior art, simplifying the step of fixing the control unit to the drum body extremely, more so easy working process can also reduce the manufacturing cost. The imaging drum, the control unit, the control unit guides