Abstract: In order to study the muscle quality of the Tibetan valley-type sheep in different parts, 10 15-month-old valley-type Tibetan sheep were randomly selected and slaughtered. The contents of crude protein, crude fat, water, calcium, iron, zinc, selenium, fat-soluble vitamin, vitamin A, vitamin E, vitamin B₁,vitamin B₂, cholesterol, fatty acid and amino acid in longissimus dorsi muscle, gluteus medius muscle and triceps brachium muscle were measured. The results showed that the water content of gluteus medius and brachial triceps was significantly higher than that of longissimus dorsi（P＜0.05）; the intramuscular fat content of longissimus dorsi and gluteus medius was significantly higher than that of brachial triceps（P＜0.05）; and the iron content of brachial triceps was significantly higher than that of longissimus dorsi（P＜0.05）, and the zinc content of brachial triceps was significantly higher than that of longissimus dorsi and gluteus medius（P＜0.05）. The contents of threonine, isoleucine, lysine, serine, glutamate and tyrosine in brachial triceps were significantly higher than those in longissimus dorsi and gluteus medius（P＜0.05）, the contents of ficocerylic acid, pentadecanoic acid, heneicosanoic acid, behenic acid, tricosanoic acid, tetracosanoic acid, tetradecenoyl carnitine, palmitoleic acid, linoleic acid, α-linolenic acid, conjugated linoleic acid-C10 C12, cis-11,14, 17-eicosentrienoic acid, arachidonic acid, Dihomogamma-Linolenic acid, eicosentaenoic acid and docosahexaenoic acid in brachial triceps were significantly higher than those of longissimus dorsi muscle（P＜0.05）, but there were no significant differences in crude protein, ash, calcium, selenium, cholesterol, vitamin A, vitamin E, vitamin B₁, vitamin B₂, essential amino acids/non-essential amino acids, essential amino acids/total amino acids, non-essential amino acids, medium-chain fatty acid, saturated fatty acid, monounsaturated fatty acids, and unsaturated fatty acid contents in longissimus dorsi, gluteus medius and brachial triceps（P＞0.05）. The results indicated that the gluteus medius muscle was better than brachial triceps and longissimus dorsi in taste and freshness, and the flavoring substance, amino acid and fatty acid composition of brachial triceps and gluteus medius were more in line with the nutritional value of human body than that of longissimus dorsi.