A fixing device includes a heating member, a pressing member, a pressing mechanism and a locking mechanism. The heating member is rotatable. The pressing roller is configured to come into contact with the heating member. The pressing mechanism is configured to convert a rotational force transmitted from a drive source to a pressing force of pressing the pressing roller against the heating member and to form a pressing region between the pressing roller and the heating member. A sheet is conveyed through the pressing region. The locking mechanism is configured to be engaged with an image forming apparatus main body linked with a pressing operation of applying the pressing force to the pressing roller and to be disengaged from the image forming apparatus main body linked with completion of a pressing release operation of removing the pressing force.