Diethylene glycol and dibutyl tin dilaurate were used to degrade polyurethane fiber waste in this paper. The glycolysis products were separated into two phases including white solid and brown liquid by a freezing process. The chemical structure and thermal property of the purified solid product were characterized by Fourier transform infrared(FTIR) spectrometer, $^1H$ nuclear magnetic resonance($^1H$ NMR) and differential scanning calorimetry(DSC). The solid product was mainly polytetrahydrofuran. The analysis of the liquid product was carried out by FTIR and high performance liquid chromatography-electrospray ionization-mass spectrometry(HPLC-ESI-MS). The liquid phase included various components such as aromatic amine, diethylene glycol-propylene diamine compound and so on. The glycolysis mechanism of polyurethane fiber waste is also discussed in this paper.