Abstract: The influences of glycolysis conditions of waste poly(ethylene terephthalate) (PET) on the hydroxyl number values and average molecular weight of glycolysis products were investigated. If at 196～198 ℃, ethylene glycol and PET weight ratio was 2, the glycolysis time was 3～3.5 h, and 1% zinc acetate was used as catalyst, PET was thoroughly glycolysed and the glycolysis products were obtained with the hydroxyl number values above 368 mg/g and the average molecular weight below 305. Bis-2-hydroxyethyl terephthalate (BHET) monomer and its oligomers were predominant glycolysis products. The products were characterized by DSC and IR spectrum.