A heating device includes a heater, a rotator, and a pressure rotator. The heater includes resistive heat generators forming a heat generation area and has a separation area formed by the resistive heat generators. The pressure rotator includes a first region and a second region. The first region faces the heater in a range of 20 mm from a center position of the heat generation area toward an end thereof in the arrangement direction. The second region faces the heater in at least a part of a range of 30 mm from a center position of the separation area toward the center position of the heat generation area. An outer diameter of the pressure rotator increases from the center toward the end. The outer diameter of the second region increases at an increasing rate larger than an increasing rate of the outer diameter of the first region.