This study was conducted in Bandare emam marine research center during the July to September of 2014. On this study effects of reducing essential amino acids of Threonine and Histidine 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 threonine and Histidine diets were deficient in threonine and Histidine respectively. At the end of the experiment the data of growth and nutritional factors were collected and fish were sampled for whole body amino acids and chemical proximate analysis. According to the results, survival rate was only decreased significantly in threonine deficient group. Growth and nutritional factors including final Wight, 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 gross energy decreased in deficient treatments. Threonine and Histidine content of whole body showed no significant different between treatments that showed amino acids sparing for these two essential amino acids. Reducing most of the growth and nutritional factor in threonine deficient diets related to the control and Histidine deficient diet showed the importance of threonine in this fish diet. Histidine reduced growth and other factors intermediary and demonstrated that there may be some mechanism for reducing Histidine consumption in deficiencies.