The GABA (γ-aminobutyric acid) content was investigated on various lactic acid bacteria and their concentration, culturing periods and energy source. Among lactic acid bacteria, Lactobacillus brevis produced 1.37-1.8 folds higher amount of GABA content by 1.8-2.0% microbial culture application. All five strains showed the increased GABA content during long culturing periods, but increased steadily GABA content at 7 days after culture. The GABA content was increased with low Lactobacillus brevis and low glutamic acid concentration and with high Lactobacillus brevis and high glutamic acid concentration. In addition, GABA content was rapidly increased by culture at 7 days after culture, but little increased for 10 days, regardless of Lactobacillus brevis and/or glutamic acid concentration. Higher amino acid powder as culture additives, showed increased GABA content. The GABA content was the highest with 475 mg 100 g^-1 at 21 days after culture with Lactobacillus brevis 2% and amino acid powder 14.5% and GABA content was increased from 21 days but decreased from 28 days, regardless of concentrations of Lactobacillus brevis and amino acid powder.