An image forming apparatus includes a heating device including a heater, a developing device, and an airflow generation device. The heater includes a base, a heat generator, an electrode portion, and conductive portions. The conductive portions are disposed on one side and another side in a longitudinal direction in a heat generation region and spaced apart in a lateral direction intersecting the longitudinal direction. A maximum total value among total values of squares of current flowing in the conductive portions at longitudinal positions on the one side is larger than that on said another side. The developing device includes a rotating member and sliding portions. A sliding portion having highest temperature in operation is disposed on one side of the developing device being same as the one side of the heater in the longitudinal direction. The airflow generation device generates an airflow toward the one side of the developing device.