The amino acid contents in brown rice of 4 medium-maturity indica sterile lines (ISL), 8 medium-maturity indica restorer lines (IRL) and 10 F1 hybrid rice were analyzed by HITACHI 8800 type auto-amino acid analyzer. The results are as follows. Amino acid contents in brown rice among F1 hybrid generation are different, of which, the total amino acids (except tryptophan) and essential amino acid contents of Mingliangyou 6, combination of Lvmin S/4HZ021and combination of Lvmin S/Fenghui35 are higher. Lysine content in combination of Lvmin S/4HZ021 is the highest. Leucine content of Mingliangyou 6 is the highest. The total amino acids (except tryptophan) and essential amino acid contents in F1 hybrid rice are higher compared with their parents, and that of hybrid combinations using Lvmin S as the female parent are the highest, while those using Lv102S as the female parent are the lowest. The influence of male parent on amino acid contents of brown rice in F1 generation was controlled by the paired maternal parent. At the same time, we should consider combining ability and other factors.