A fixation unit that fixes toner onto a recording paper includes a thermal fixation roller, a heating part that heats the thermal fixation roller, a compressing part that presses the thermal fixation roller, and a drive gear, mounted on the thermal fixation roller, which rotationally drives the thermal fixation roller, wherein an outer diameter of the thermal fixation roller is equal to or larger than an inner diameter of the drive gear, as the heating part heats the thermal fixation roller.