Abstract:In order to study and promote the advantages of excellent breeds and better serve the promotion and application of seed selection, breeding and mutton production performance, this study selected three breeds of valleytype Tibetan sheep, Qinghai semifine wool sheep and Qinghai Tibetan sheep, and Jie sheep of different ages. We carry out muscle nutrient composition analysis and amino acid content determination. The results show that the main nutritional indicators and testing data of valleytype Tibetan sheep are crude protein content of 21.00%, crude fat 3.15%, cholesterol 0.3650 (mg/g), volatile base nitrogen 0.1190 (mg/g), and total mineral content 6 785 (mg/g), energy is 4.74 (kJ/g). Its total amino acid content is 16.08% higher than Qinghai semifine wool sheep and 5.06% higher than Qinghai Tibetan sheep. The conclusion of this study is that the content of volatile basic acids can reflect the freshness of mutton, and anything within 0.15mg/g is considered fresh. This shows that the mutton tested in this analysis has high energy, high protein, low fat, low cholesterol and rich amino acid content, and is a pollutionfree food.