An image forming apparatus includes an image bearer; a charger to charge a surface of the image bearer; an exposure device to expose the surface of the image bearer and form an electrostatic latent image on the image bearer; a developing device to adhere electrically charged toner to the electrostatic latent image on the image bearer, to thereby form a toner image; a microprocessor to control rotation of the image bearer; and a sensor to detect temperature and humidity. In a state of suspended rotation of the image bearer, the microprocessor controls the image bearer to rotate a predetermined amount at a predetermined interval and determines whether a rotation operation of the image bearer is to be performed, based on a detection result of the sensor.