Abstract: According to the present disclosure, a heat treatment apparatus includes a heating treatment unit that heat-treats a strip-shaped sheet while transferring the strip-shaped sheet, and a cooling unit that cools the strip-shaped sheet having been heat-treated in the heating treatment unit while transferring the strip-shaped sheet. The cooling unit includes a cooling roller that allows a refrigerant to flow through the inside thereof, and an outer wall that surrounds the space in which the cooling roller is disposed. The heat treatment apparatus may further include a take-up unit in which the strip-shaped sheet having been cooled in the cooling unit is wound.