A heating apparatus of an electromagnetic induction heating type includes
a coil and a roller which generates heat by the action of magnetic flux
generated from the coil. A recording material is heated by the roller.
The heating apparatus further includes a movable magnetic flux decreasing
member for decreasing magnetic flux, generated from the coil, acting on
the roller. In the heating apparatus, a shutter is moved toward an
effective position at which a temperature in a non-conveyance area is
lowered when a recording material having a size lower than a maximum
conveyable size is conveyed, and is moved away from the effective
position depending on the temperature in the non-conveyance area,
irrespective of the size of the recording material to be conveyed.