A fixing device has a heating rotor, a pressure belt, a sheet member, first and second pressurizing members, a motor and a control unit. The control unit controls the motor to rotate the heating rotor and the pressure belt in a direction opposite to a conveyance direction of a recording material at startup time after jam treatment of the recording material. Contact positions of the sheet member with respect to the first and second pressurizing members are changed, so that the sheet member is prevented from obstructing independent actions of each of the first and second pressurizing members, which allows the nip portion N to maintain proper nip width and proper nip pressure. Thus, the fixing device has excellent stability at the nip portion to improve fixability and conveyability of the recording material with a simple construction.