Abstract:A pot experiment was carried out to investigate the effects of 5 different treatments of mixed application of calcium magnesium phosphate and aminoacid foliar fertilizer on Se availability in acid Se-rich soil, Se contents in different rice organs, and organic Se in rice grains. 6 treatments were designed: 1)CK,conventional calcium magnesium phosphate, 0.2 g/kg; 2) P1, single low calcium magnesium phosphate, 0.4 g/kg; 3) P2, single high calcium magnesium phosphate, 0.6 g/kg; 4)B, single aminoacid foliar fertilizer; 1 500 ml/hm2; 5) P1+B; 6) P2+B. The results showed that all treatments increased significantly soil Se availability and organic Se contents in rice grains compared with CK (P <0.01), the effects of P2 and P2+B treatments were best, which increased available Se contents by 42.16 μg/kg and 43.54 μg/kg, respectively, increased organic Se contents in rice grains by 28.65 μg/kg and 39.27 μg/kg, respectively.