suggested that 0.3–0.6 mg folic acid/kg diet was optimum for young rainbow trout based on survival and growth, and that was 1.1 mg folic acid/kg diet based on tissue folic acid saturation. pointed out that 0.5–1.0 mg folic acid/kg dietwasoptimum for Nile tilapia based on growth response and hematology. concluded that the optimal dietary folic acid level for juvenile grouper was about 0.8 mg/kg based on the analyses of weight gain, hepatosomatic index, hepatic folic acid concentration and hepatic thiobarbituric acid-reactive substance value.