The present invention relates to a polyester resin and a manufacturing method thereof. Specifically, an embodiment of the present invention provides a polyester resin consisting of a copolymer of a monomer mixture including a furan dicarboxylic acid-based compound, an aliphatic diol-based compound, and a lactone-based compound.

Bis(glycol) terephthalate is prepared by transesterification of bis(2-hydroxyethyl) terephthalate, which is a recycled monomer obtained by depolymerization of a waste polyester, and a glycol having at least 3 carbon atoms, and then is copolymerized, and thus can increase the amount of recycled monomers in a polyester resin, and has improved purity through the removal of impurities during transesterification, thereby enhancing final resin quality such as color.

Bis(glycol) terephthalate is prepared by transesterification of bis(2-hydroxyethyl) terephthalate, which is a recycled monomer obtained by depolymerization of a waste polyester, and a glycol having at least 3 carbon atoms, and then is copolymerized, and thus can increase the amount of recycled monomers in a polyester resin, and has improved purity through the removal of impurities during transesterification, thereby enhancing final resin quality such as color.