A biaxially oriented polyester film is provided, in particular, a biaxially oriented polyester film for molded part capable of being used suitably as a metallic molded part processed after metal deposition on a film surface and a surface protection film in forming a decorative sheet. Provided is a biaxially oriented polyester film for molded part, which is a polyester film that at least two layers of A layer composed of polyester A and B layer composed of polyester B are laminated, wherein interlayer adhesion between A layer and B layer is 5 (N/15 mm) or more, and stress at 100% elongation (F100 value, unit: MPa) at 200° C. and 150° C. in the longitudinal direction and transverse direction of a film is 1 to 50.