The invention aims to prevent an image deterioration resulting from a fixing belt rising in temperature too much, and prevent heat of the fixing belt from being transmitted to peripheral members around a fixing apparatus such as a photosensitive drum so as not to adversely effect the peripheral members. A fixing apparatus 5 has a fixing roller 510 and a fixing belt 531 that heat-fix an image on to a recording material P by a fixing nip W, partition walls 601 to 605 that surround the fixing belt 531 to thereby suppress the air naturally entering into around the fixing belt 531, and a cooling unit that cools the fixing belt 531 in a closed space 600 formed by the partition walls 601 to 605. The cooling unit has a supply duct 612 through which a supply fan 613 supplies air to the closed space 600 from below, a cooling fan 611 that blows the air supplied from the supply duct 612 toward the fixing belt 531, and a discharge duct 614 through which a discharge fan 615 discharges the air from an upper portion of the closed space 600.