Previous studies of the banding mechanism have proposed various reduction methods for the electrophotographic process. The banding mechanism is generally caused by vibration transmitted by the drive system and the resulting resonance. We analyzed banding that occurred in a single-component contact development system, and it became clear that banding was caused by self-excited vibration. Our self-excited vibration model consists of the following elements: a spring element (the rubber layer of the development roller), a mass element (the development unit), and an exciting force (the friction between the development roller and the OPC drum). We also observed that the model's vibration frequency varies nonlinearly, an interesting characteristic caused by the nonlinear hardening properties of the spring. Since self-excited vibration can be prevented by stabilizing the system, we propose the use of appropriate damping components. We also statistically verified the banding reduction effect by conducting quantitative analysis of vibration intensity.