To provide an image forming device capable of cooling an image forming unit while preventing toner scattering and of reducing toner contamination in operations such as part replacements.

On the left surface side of a device body, axial fans 15a and 15b for taking in outside air are disposed in two places. The outside air flowing in passes between an upper partition plate 33 and a writing unit 11 to cool a lower surface side of each image forming unit 6 and flows upward to enter into an exhaust duct 38 formed on the rear surface of a cover 37a of a positioning member 37 of the image forming unit which is provided on the front side of the device. The air is sucked by a sirocco fan 39 and exhausted to the outside of the device through exhaust ducts 40 and 41. The exhaust duct 38 is positioned below a handle part of a toner bottle arranged at an upper part of the image forming unit 6.