An image forming apparatus may include an apparatus body, and a photosensitive-member unit slidably attached to the apparatus body and retaining a plurality of photosensitive members. The apparatus body includes side wall portions opposing each other with a unit receiving section sandwiched therebetween, and a plurality of apparatus-body-side electrode members provided on the side wall portions, and each urged inward in an opposing direction of the side wall portions. The photosensitive-member unit includes a plurality of unit-side electrode members each protruding outward in the opposite direction and a guide path comprising a flat surface formed in a flat shape so that each of the apparatus-body-side electrode members slidably contacts to the flat surface during attachment of the photosensitive-member unit with respect to the unit receiving section, and that each of the apparatus-body-side electrode members slidably contacted maintains a constant inward and outward position in the opposite direction.