A charging device which has a grid disposed between a discharge element and the photosensitive drum. The grid is formed of a regulating portion having a mesh configuration for the range opposing the image area on the photosensitive drum and non-regulating portions with openings for the range opposing the non-image area. The flow of ions discharged from the discharge element is regulated as to their passage through the grid thereby so as to be uniform and charge the image area on the photosensitive drum uniformly. The flow of ions reaches the non-image area without being shaded by the grid, so as to enhance the surface potential for prevention against toner adherence.