The study on efficacy of different manganese source for on growth performance, immunity and deposition in bone of Asian seabass (Lates calcarifer) was assigned in CRD with 5 treatments and 3 replicates. The treatments were control without manganese supplementation. The other three treatments of manganese were 10 ppm at different form of inorganic (oxide, chloride, sulfate) and manganese amino acid(Availa-Mn) 10 ppm. Asian seabass with average weight of 24.67±1.09 g were stocked in 500 liter tanks at the density of 10 fishes per tank and fed treatment diet 3% of body weight twice daily for 12 weeks. The results showed that there were statistical differences (P<0.05) on growth performance in term of weight gain, average daily gain, specific growth rate and feed conversion ratio. The growth performance of Asian seabass fed diet supplemental organic Availa-Mn was higher than the other groups (P<0.05). The immunity in term of erythrocyte count, leucocyte count, hemoglobin, serum protein and immunoglobulin (IgM) showed no significantly differences (P>0.05). The deposition of manganese in bone of Asian seabass fed diet supplemental organic Availa-Mn was numerical higher than the other groups but was not significantly differences (P<0.05). Therefore, supplementation organic manganese amino acid(Availa-Mn) in Asian seabass diet can promote growth performance and manganese accumulation in bone better than inorganic form.