An image-forming apparatus forms an image by applying a control electric field having a polarity corresponding to recording information, to a recording medium having microcapsules including chargeable particles dispersed in a dispersion medium. The image-forming apparatus includes an alternating electric field-applying unit for applying an alternating electric field to the microcapsules. The alternating electric field is applied to the microcapsules of the recording medium before the image formed on the recording medium is rewritten. Accordingly, the chargeable particles are separated from the wall surfaces of the microcapsules and from the other chargeable particles, making it possible for the chargeable particles to perform free electrophoresis. The recording medium is initialized to improve the response performance with respect to the control electric field for forming a new image. The recording density is increased, and the blur is reduced.