An image forming apparatus has a heat member configured so that a
longitudinal center becomes a conveyance center of the recording
material, the apparatus also having a central portion temperature
detection part for detecting a temperature of the heat member
corresponding to the conveyance center or adjacent thereto, a one side
end portion temperature detection part for detecting one end portion
temperature at one side in a longitudinal direction of the heat member,
and an other side end portion temperature detection part for detecting an
other end portion temperature on the other side in the longitudinal
direction of the heat member, and a control part for controlling the
image forming apparatus based on heat member temperature information
detected by the central portion temperature detection part, the one side
end portion temperature detection part, and the other side end portion
temperature detection part.