For start of rotation of a fixing roller that is not currently being rotated, a control device causes a halogen lamp to heat an endless belt until a thermistor detects that a surface temperature of the endless belt has reached a first target temperature set at a temperature at which the endless belt is softened and is restored to its normal shape, from a deformed shape that the endless belt had while it was not rotated, to such an extent that the endless belt will never cause any rotation trouble during the rotation. This prevents the rotation trouble of the belt in a fixing apparatus in which a fixing member is heated by bringing the thus heated belt into contact with the fixing member.