Fixing Device, Image Forming Apparatus

A fixing device that can suppress UFP generation includes a heating roller, a heater, and a dust preventing member. The heating roller is larger in width than a maximum paper passing region through which a sheet of a predetermined maximum size passes. The heater heats the heating roller. The dust preventing member is provided in an inner layer part of the heating roller between a paper non-passing region and a rotation shaft of the heating roller, the paper non-passing region being located outside the maximum paper passing region in an axis direction of the rotation shaft. The dust preventing member is made of a material from which UFPs are not generated or are difficult to be generated in a temperature environment in which the dust preventing member is heated and can reach a predetermined temperature at most.