Abstract: Objective To determine the contents of 18 kinds of amino acids in muscle of Tinca tinca,Esox lucius,Perca fluviatilis,Thymallus arcticus and Lota lota living in the Irtysh River and evaluate the nutritional quality.MethodUsing acid hydrolysis and alkaline hydrolysis.ResultTheir total amino acids composition vary from 82.65;to 59.37,of which Thymallus arcticus was lower than the others signally;Mass fraction of essential amino acids varied from 53.52;to 39.95;,except Tinca tinca and Esox lucius,the other three species showed a remarkable difference;Delicious amino acids composition varied from 34.99;to 26.37;,of which Thymallus arcticus and Tinca tinca were lower than the others notably.Compared with the ideal pattern of WHO/FAO,they showed a fine fitness of the essential amino acids composition in the five fishes.RC of the five fishes was 93.27;-83.33;.ConclusionThese five kinds of fish contain rich amino acids and a balanced essential amino acids proportion,and they also have a high proportion of delicious amino acids.The nutritional value order of the five kinds of fish is: Tinca tinca>Esox lucius>Erca fluviatilis>Thymallus arcticus>Lota lota evaluated by the ratio of amino acid to the reference point and in the meanwhile they reach the specification of commercial fish.