A thermal fixing device includes: a fixing member configured to be in
contact with a fixation medium; a first pressing member disposed to face
the fixing member and presses the fixation medium to the fixing member; a
second pressing member disposed to face the fixing member at a position
downstream in a conveyance direction of the fixation medium with respect
to the first pressing member and presses the fixation medium to the
fixing member; and a changeover unit configured to change over a pressing
force per unit area of at least one of the first pressing member and the
second pressing member.