An image forming apparatus including a fusing belt, a pressure roller disposed to face the fusing belt so as to press a recording medium onto the fusing belt, a nip forming member to support an inner surface of the fusing belt so as to form a fusing nip along with the pressure roller, and a heat source disposed inside the fusing belt to simultaneously apply radiant heat to the fusing belt and the nip forming member. The nip forming member includes a hill portion, which is located to one side thereof farther downstream in a movement direction of the recording medium and protrudes toward the hill portion. The hill portion causes the recording medium, which has curled in a given direction, to be bent in an opposite direction immediately prior to exiting from between the nip forming member and the pressure roller, thereby reducing curling of the recording medium.