γ-amino butyric acid (GABA) is a non-protein amino acid widely distributed in nature. It has analgesic effect,promotes growth hormone secretion and prevents the physiological function of Alzheimer's disease.In order toimprove the yield of GABA, the strain of strain HX-3-6 was tested by Atmospheric and Room Temperature Plasma(ARTP), and the strain with more than 90% lethality was selected for fermentation, and through the gradient plateaccording to the level of GABA concentration and colony size of the screening. Then, use the fermentation mediumfor re-screening and genetic stability test. The yield of the mutant strain L-120-1 was 5.828 g/L, which was 18.84%higher than that before the mutation (4.904). The mutant strain L-120-1 was used as the starting strain for ARTPmutagenesis. The yield of the stable mutant strain 90s-high was 6.178g / L, which was 16.15% higher than that beforethe mutation (5.319g / L). The yield of HX-3-6 strain was higher than that of GABA mutant strain 90s-high 2, whichwas stable and high yield GABA was 25.98%.