A fixing device includes a fixing belt, a pressuring member, a pressing member, a heat source and a heat transmitting member. The fixing belt is arranged rotatably. The pressuring member is arranged rotatably to come into pressure contact with the fixing belt so as to form a fixing nip. The pressing member presses the fixing belt to a side of the pressuring member. The heat source is arranged at the inside in a radial direction of the fixing belt to radiate a radiant heat. The heat transmitting member comes into contact with an inner circumference face of the fixing belt to absorb the radiant heat radiated from the heat source. A part of the heat transmitting member is sandwiched between the fixing belt and the pressing member.