Lysine and methionine are commonly the most important amino acids in feed ingredients used in commercial fish diet. These limitations increase by replacements of fish meal with plant protein sources. This study was conducted in Bandare Emam marine research center during the July to September of 2014. In this study, the effects of reducing essential amino acids of lysine and methionine in diets of Sobaity seabream in a constant level on whole body amino acids and chemical proximate, growth and nutritional indices was assessed. For these purposes three different treatments in triplicate was used during 42 days in base of feeding with semipurified diets containing crystalline amino acids. The control diet was without any deficiency, the lysine and methionine diets were deficient in lysine and methionine, respectively. According to the results there were no significant differences between treatments for survival rate but growth and nutritional factors including final weight, percentage of weight increase, specific growth rate, protein efficiency, nitrogen retention and also intraperitoneal fat were decreased in deficient diets related to the control but feed conversion ratio increased. Crude lipid and methionine content of whole body decreased in deficient diets but there was no significant difference in lysine. The most reducing in the growth and nutritional factor in deficient diets related to the control indicating the importance of lysine and methionine essential amino acids in this fish. Methionine and lysine amino acids are contributors of lipid metabolism and deposition in Sobaity seabream.