Abstract: Effects of germination temperature, soaking time, germination time and concentration on proteinase activity in brown rice by using central composite design were investigated.The predictive polynomial quadratic equations model was developed, and optimal condition dynamic changes of proteinase activities in brown rice during sprouting period could be concluded as follows:germination time 24h, soaking time 9h, germination temperature 30℃, concentration of sodium selenite 20mg/L, on these conditions, the protease activity was up to 5.09U, and meanwhile the content ofγ-aminobutyric acid (GABA) was 144.33mg/100g determined by HPLC, the results showed that the content of GABA in brown rice after germination was much higher than before germination (5.12mg/100g) , organic-Se was 0.376mg/kg.