The present invention comprises a photosensitive member supported for rotation within a unit case and a charger for uniformly charging the photosensitive member. The charger includes a conductive member in the form of a sheet held in contact with the photosensitive member and a supporting member having a non-flat cross section for supporting the conductive member, in which the charger applies a voltage formed of a direct-current voltage with an alternating-current voltage added thereto to the conductive member to thereby uniformly charge the photosensitive member. The charger is kept in place by having the supporting member fixed to vertical planes of the unit case at positions off vertical planes crossing the photosensitive member. Thus, rigidity of both the supporting member itself and that of the portions where the supporting member and the unit case are fixed together are made higher and, in addition, the portions where the supporting member and the unit case are fixed together are positioned off the portion on which a varying attractive force between the photosensitive member and the conductive member acts. Accordingly, the unit case hardly vibrates and noise is hardly produced.