Abstract: A copolymer polyester resin and a preparation method therefor are disclosed. The copolymer polyester resin contains a repeating unit derived from diol components and a repeating unit derived from a component of dicarboxylic acid or a derivative thereof, in which, by adjustment of the amounts of a first diol to a third diol or a fourth diol to a sixth diol, included in the diol components, impact strength and intrinsic viscosity are controlled to be within appropriate ranges without degrading transparency, and thus miscibility is excellent. Therefore, the copolymer polyester resin can exhibit excellent characteristics when utilized in various fields requiring high impact strength and high heat resistance, such as packaging materials such as food containers, and interior materials for vehicles.

Abstract: The polyester copolymer according to the present disclosure is excellent in processability, particularly in shear thinning characteristics, and thus can be applied to the production of various transparent containers by an EBM process.