An image forming apparatus includes a stacking unit, a feeding unit, an image forming unit, a discharge stacking unit, a detecting unit, a double-side feeding passage, and a controller. In a case that subsequent to a current recording material, a subsequent recording material is discharged, the controller determines a feeding timing of the subsequent recording material depending on a discharge interval time from discharge of the current recording material on the discharge stacking unit to discharge of the subsequent recording material on the discharge stacking unit, and determines the discharge interval time on the basis of print information of at least the subsequent recording material.