An image forming apparatus to and from which a replenishment container accommodating toner is attachable and detachable includes an opening/closing portion moving from a closed position to an open position in a case where the toner replenishment container attached to a replenishment port is rotated, and a locking membered to move between a restricting position restricting movement of the opening/closing portion from the closed position to the open position, and an allowing position in which the movement of the opening/closing portion from the closed position to the open position is allowed. In addition, a controller, in a case where a replenishment operation, in which toner is supplied from the replenishment container to the replenishment port, displays, on a display, a ratio corresponding to an amount of toner accommodated in the developer container after the replenishment operation.