It is provided that a polyester film containing a polyester resin obtained by recycling PET bottles and having high lamination strength and slight unevenness in thickness. A biaxially stretched polyester film comprising 50 wt. % or more and 95 wt. % or less of a polyester resin obtained by recycling PET bottles, wherein the content of an isophthalic acid component in all dicarboxylic acid components in the entire polyester resin composing the polyester film is 0.5 mol % or more and 5.0 mol % or less, and the polyester satisfy the specific intrinsic viscosity, the specific thermal shrinkage rate, the specific refractive index in the thickness direction, and the specific unevenness in thickness.