To investigate the effects of methionine and lysine supplementation on growth performance，transaminase，body composition and antioxidant performance of juvenile Micropterus Salmoides，three dietary protein gradients （46% （control），41% （LP1） and 36% （LP2）） were set.On the basis of 41% and 36% protein diets，crystal lysine and methionine were supplemented to keep the contents of lysine and methionine consistent with the control group，which were recorded as LP1+AA group and LP2+AA group，respectively.Each experimental group contained 3 biological replicates and the feeding period was 8 weeks.The results showed as follows：compared with the control group，there were no significant differences in weight gain rate （WGR），specific growth rate （SGR），feed conversion ratio （FCR） and protein retention （PR） in LP1+AA group，but significant changes were observed in other groups.With the decrease of protein level，crude protein content in muscle and whole body was significantly decreased，but not in LP1+AA group compared with the control group.There was no significant change in crude fat and ash content.The hepatosomatic ratio （HSI） in low protein diet group was significantly decreased，but there was no significant decrease in LP1+AA group compared with the control group.Compared with the control group，the levels of liver reactive oxygen species （ROS） and total antioxidant capacity （T-AOC） of fish in LP2 and LP2+AA groups were significantly changed.The T-AOC of liver in LP1 group was significantly decreased，but it was significantly increased in lysine and methionine supplementation groups.Reducing dietary protein level （5% or 10%） had no significant effect on liver transaminase activity.Although serum glutamic-pyruvic transaminase （GPT） activity changed significantly in LP2 group，there was no significant difference when lysine and methionine were added compared with the control group.The results showed that when dietary protein content was reduced from 46% to 41% and supplemented with essential amino acids，the growth performance was not significantly affected，but when the dietary protein content was reduced to 36%，lysine and methionine supplementation could not effectively alleviate the negative effects of low dietary protein on growth performance.