A fixing device (50) includes a fixing belt (70), a pressure member (80), and a heating section (90). The heating section (90) faces an inner peripheral surface of the fixing belt (70). The heating section (90) includes a heater (HT), a first heat sensitive body (SM11), and a second heat sensitive body (SM21). The second heat sensitive body (SM21) differs from the first heat sensitive body (SM11). The heater (HT) has a first heater portion (AE1). The first heater portion (AE1) is one end portion of a pair of end portions of the heater (HT) in a longitudinal direction thereof. The first heat sensitive body (SM11) and the second heat sensitive body (SM21) face the first heater portion (AE1) and are aligned in a conveyance direction (DC) of a sheet (S).