IMAGE FORMING APPARATUS

PROBLEM TO BE SOLVED: To provide an image forming apparatus which is capable of suppressing a failure caused by toner adhering to a photoreceptor, when the application of a voltage from a common power supply is started, in such a configuration that the voltage is applied to electrifying means and developing means from the common power supply.SOLUTION: An image forming apparatus 100 includes a photoreceptor 1, electrifying means 2, exposure means 3, developing means 4, a common electrification/development power supply 130 applying the voltage to the electrifying means 2 and the developing means 4, a movable rotary body 71 which forms a transfer part Nt together with the photoreceptor 1 and to which a toner image is transferred from the photoreceptor 1, and a control part 150 controlling the potential in the transfer part Nt of the rotary body 71. The image forming apparatus 100 is configured so that when the rotation of the photoreceptor 1 is started, the control part 150 performs controlling so that the potential in the transfer part Nt of the rotary body 71 becomes the potential having the same polarity as the electrification polarity of the toner during development until an electrification processing part on the photoreceptor 1 reaches the transfer part Nt from the time when the output of the electrification/development power supply 140 is started.