Abstract: This study was performed to determine the content and constituents of amino acids in Cordyceps Sinensis from different regions of Tibet and evaluate the nutrition, so as to provide the scientific basis for utilization of those materials and further research. The samples were hydrolyzed by HCl and analyzed by automatic amino acid analyzer; the nutritional value was evaluated using amino ratio coefficient. All samples included 17 amino acids, 7 essential amino acids, 4 umami tasty amino acids, 9 medicinal amino acids. The total amino acids in Cordyceps Sinensis from different regions of Tibet ranged from 23.4% to 24.52% , the essential amino acids took up 26.47%-27.52% of the total amino acids, the umami tasty amino acids took up 35.12%-37.44% of the total amino acids, and the medicinal amino acids took up 55.03%-57.54% of the total amino acids. With amino ratio coefficient, the first limiting amino acids were Met+Cys. SCR ranged from 66.0 to 69.7. The content and constituents of amino acids in Cordyceps Sinensis from different regions of Tibet had no significant difference, the essential amino acids was relatively balanced and reasonable. Compared with Cordyceps Sinensis from different regions of Tibet, the Cordyceps Sinensis from Qamdo had higher trophic value than the others.