Abstract: In this study, 20 tibetan sheep each from Tibetan Autonomous Prefecture of Gannan（Gansu province） and Haibei（Qinghai province） were selected as subjects, and the meat qualities, fatty acids, volatile substances compositions, and sensory evaluation of the longissimus dorsi were determined for each sample, in order to evaluate the volatile flavor substances and fatty acid compositions of tibetan mutton from different regions. The results showed that the pH45min and p H24h values of both regions of tibetan sheep after slaughtering fell within the normal range with no significant between-group difference. However, Gannan tibetan mutton exhibited superior color and tenderness characteristics compared with Haibei mutton, and a total of 18 fatty acids were detected out in both types of tibetan mutton, including 7 saturated fatty acids and 11 unsaturated fatty acids. Gannan tibetan mutton presented a lower ω-6/ω-3 ratio（close to 1∶1） compared with Haibei mutton（P＜0.05）, indicating a better fatty acid composition ratio. Furthermore, a total of 70 volatile flavor substances belonging to 12 categories were identified in the samples. Odor activity value（OAV） analysis revealed that Gannan tibetan mutton possessed richer meaty and fruity flavors than Haibei tibetan mutton. In conclusion, Gannan tibetan mutton demonstrated superior fatty acid and volatile compositions compared to Haibei tibetan mutton, which also obtained higher sensory scores.