Abstract: For recycling the enzyme-alkali unhairing method in yak leather making process, sodium sulfide and lime were replenished during the effluent recycling based on analysis data. The COD value and protein content in every recycling effluent were tested, and the swelling rate together with fiber opening of limed pelts were also measured to evaluate the influence of recycling process on liming effect. At last, the mechanical and organoleptic properties were tested when the pelts were converted into crust to clarify whether effluent recycling affected leather properties. The results showed that 41.23% sodium sulfide, 46.16% lime and 70.00% water were saved during 11 times recycling. The COD and protein content in effluent trended to stable after 9 times recycling, but the swelling rate and fiber opening decreased, and some hair roots remained after liming. In addition, the mechanical properties and grain cleanliness also become poor after 9 times recycling. In short, this effluent could be used, and the optimum recycling would be 9 times.