An exposure device includes light emitting elements, a driving circuit, an image-signal connector, a power connector, and an adjustment-control-signal connector. The light emitting elements emit light which an exposure target member is exposed to. The driving circuit performs one of first and second drive operations. The image-signal connector has terminals connected to core wires of an image-signal cable, and relays, to the driving circuit, image signals transmitted through the image-signal cable. In the image-signal cable, the core wires are arranged at a first pitch. The power connector has terminals arranged at a pitch wider than the first pitch, and relays, to the driving circuit, power transmitted through power cables. The adjustment-control-signal connector has terminals arranged at a pitch wider than the first pitch, and relays, to the driving circuit, light-amount adjustment control signals transmitted through adjustment-control-signal cables.