A continuous culture method of Lactobacillus brevis NCL912 was developed for production of γ-aminobutyric acid.The effects of the dilution rate on the biomass,residual glucose and GABA yielding of the continuous culture were investigated.The results indicated that dilution rate had a significant effect on the cell proliferation and GABA production.Steady state could not be obtained when dilution rates were 0.06 h-1 or 0.14 h-1.When dilution rates were 0.08 h-1,0.10 h-1 or 0.12 h-1,the culture system could reach the steady states.Among the dilution rates tested,0.10 h-1 was the best one for the GABA continuous production.