Abstract: By changing type and proportion of ingredients and supplying amino acids, six dietary EAA patterns are designed, in which Dietary Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ and Ⅵ respectively are in 0.7071,0.7259,0.7409,0.7512,0.7827 and 0.8231 relativity of EAA equilibrium. The purpose of the experimental design is to study effects of dietary EAA balance on the growth and protein synthesis and degradation in muscle and hepatopancreas of grass carp. Results show that: 1. The balanced EAA pattern enforce growth of grass carp and transformation of feeds. 2. The balanced EAA pattern can increase protein synthesis and degradation rate (FSR, FDR) and fractional protein growth rate (FGR) of muscular organism and hepatopancreas, but following the change of EAA pattern in diets, protein retention efficiency (PRE), that is FSR/FDR, and translational efficiency of protein synthesis (KRNA) didn't show significant diference. 3. For the muscular orginism, relationships between FGR?FSR? FDR and relativity of EAA equilibrium is: YFGR=3.7487x-1.3991 (r=0.9445), YFSR=18.734x-7.4771 (r=0.9597), YFDR=14.985x- 6.078 (r=0.9625), respectively. 4. For the hepatopancreas, relationships between FGR、FSR、FDR and relativity of EAA equilibrium is: YFGR =4.2788x-1.6545 (r=0.9399),YFSR=43.262x-16.207 (r=0.9315),YFDR=38.983x-14.553 (r= 0.9303) respectively. 5. In the six dietary EAA patterns, FSR and FDR in the hepatopancreas are remarkably higher than in the muscular orginism. 6. The balanced EAA pattern can stimulate a positive protein growth, partially attributing to increased protein synthesis capacity, greater difference between synthesis and degradation.