An image forming apparatus includes first and second rotatable members forming a nip therebetween, a heater disposed in inside of the second rotatable member, a first temperature sensor provided on a center of the heater, a second temperature sensor provided on an end side of the heater. A controller controls a feeding interval in which a trailing edge of a preceding sheet passes through the nip until a leading edge of a subsequent sheet reaches the nip. The controller controls the feeding interval to be a first interval in a case which a feeding speed of the sheet is a first speed and a detected temperature by the second sensor is a first temperature, and to be a second interval shorter than the first interval in a case which the feeding speed is a second speed lower than the first speed and the detected temperature is the first temperature.