〔Abstract〕 Objective To prepare a recombinant PETase with a dual-catalytic-triad and to evaluate its efficiency in the biodegradation of polyethylene terephthalate（PET）. Methods Based on the crystal structure of wild-type PETase，point mutations（T88H/L 117D）were introduced via site-directed mutagenesis. The recombinant protein was prepared using prokaryotic expression and chromatography purification techniques. The enzymatic hydrolysis of the mutant PETase was assessed by relatively quantifying the products mono（2-hydroxyethyl）terephthalate （MHET）and terephthalic acid（TPA）. Results Both wild-type and mutant PETases accumulated as inclusion bodies，accounting for approximately 20% of the total bacterial protein. After solubilization in urea，the proteins were eluted at 300 mmol/L imidazole during affinity chromatography purification，with concentrations of 1. 824 and 1. 833 mg/mL and purities of 83. 11% and 84. 32%，respectively. Subsequent anion-exchange chromatography yielded highly pure enzymes in the 200 mmol/L NaCl fraction：2. 776 mg/mL（96. 86% purity）for the wild type and 1. 967 mg/mL（95. 13% purity）for the mutant. Following refolding，the final concentrations were 0. 484 mg/ mL for the wild type and 0. 991 mg/mL for the mutant. Hydrolysis assays revealed that the mutant released MHET and TPA at（237. 67± 17. 00）% and（197. 33± 12. 01）% of the wild-type levels，respectively. Conclusion The T88H/L 117D dual-catalytic-triad PETase is successfully prepared and it significantly enhanced PET-degrading ac⁃ tivity，thus，it's a promising biocatalyst for PET bioremediation.