Toner having spindle-shaped particles is used to form images in an image forming apparatus. Each spindle-shaped particle has a ratio of a length in a minor axis to a length in a major axis in a range from 0.5 to 0.8 and a ratio of a thickness to the length in the minor axis in a range from 0.7 to 1.0. A charging device applies an electric charge onto an electrostatic latent-image carrier of the image forming apparatus. The charging device includes a charging roller, a surface roughness of which is equal to or smaller than 10 micrometers.