Abstract:This study was conducted to estimate essential amino acids (EAA) requirements of juvenile Barbus capito.Feeding experiments of B.capito ((11.29±0.07)g) were conducted with the protein diets (PD) and protein-free diets (FPD) and each diet was randomly assigned in triplicate.The EAA requirements of B.capito were determined based on the daily increment and daily maintenance requirement of each EAA in fish body.Compared with the PD group,the final weight and specific growth rate decreased significantly (P<0.05) and the whole body moisture content increased significantly (P<0.05) in the FPD group.When dietary protein level was 43%,feed utilization rate was 90% and feeding rate was 3%,the daily EAA requirements of juvenile B.capito (mg/100 g body weight) were as follows:phenylalanine 25.54,methionine 15.80,arginine 36.08,lysine 53.76,leucine 49.95,threonine 25.05,valine 25.99,isoleuline 25.33 and histidine 19.94.The requirements of EAA for B.capito feed (g/100) were as follows:phenylalanine 0.85,methionine 0.53,arginine 1.20,lysine 1.79,leucine 1.67,threonine 0.84,valine 0.87,isoleuline 0.84 and histidine 0.66.