Abstract: In order to study the effects of freezing-thawing times on the quality characteristics of frozen mutton. After freezing and thawing repeatedly for 0, 1, 3, 5 times and then refrigerated at 4 ℃ for 1, 3, 5, 7 days, the nutritional quality, edible quality, texture characteristics and lipid oxidation degree of Oula Tibetan mutton were determined. The results showed that with the increase of freeze-thaw times, the nutritional quality of Tibetan mutton deteriorated significantly, the moisture content and protein content decreased significantly (P < 0.05); The overall eating quality of Tibetan mutton decreased significantly, especially after 5 freeze-thaw cycles, the color stability and water holding capacity decreased significantly (P < 0.05), the tenderness decreased slightly, but the change was not significant, and the meat hardness and chewiness decreased, while the viscosity, elasticity and adhesiveness increased; Meanwhile, peroxide value (POV) and thiobarbituric acid value (TBARS) reached the maximum after 5 freeze-thaw cycles (P < 0.05), indicating that the degree of lipid oxidation increased with the increase of freeze-thaw cycles; At the same time, the longer the cold storage time, the worse the meat quality. The above results showed that the increase of freeze-thaw cycles had a great impact on the meat quality, and the repeated freeze-thaw phenomenon should be avoided in the actual production, processing and transportation of meat.