Method of preparing a polyester copolymerized resin 1,4-cyclohexanedimethanol.

A method for preparing polyester resins copolymerized with 1, 4-cyclohexanedimethanol comprising the steps of: esterifying terephthalic acid with a glycol component comprising ethylene glycol and 1, 4-cyclohexanedimethanol; and polycondensing said esterified reaction product of 250 to 290 ° C under reduced pressure of from 53,300 to 13, 3 Pa (400 to 0, 1 mmHg) in the presence of a compound based on titanium as a polycondensation catalyst and a triethylphosphonoacetate as a stabilizer and the the 1, 4-cyclohexanedimethanol amounts to 10 to 90 mol% of total glycol component, and wherein the triethylphosphonoacetate is used in an amount of 10 to 150 ppm of P element based on the final polymer.