A Bacillus amyloliquefaciens strain SWJS22 isolated from deep sea mud of the South China Sea was used to produce glutaminase by solid-state fermentation. Using single factor test and orthogonal test, including culture media and the fermentation parameters, was applied to optimize glutaminase production technology; optimal fermentation conditions were: 2% (V/m) seed liquid was inoculated in a culture medium composed of 20 g soy flakes, 5 g wheat flour, 0.02 g SE-1170, water to solid in a ratio of 1.0∶0.6 (m∶m), and fermented at 37 ℃ for 48 h. Under this optimized condition, the L-glutaminase activity was increased from （83.10±4.64） U/mgds to （2 690.02±28.80） U/mgds. The extraction of glutaminase was also optimized, the optimal extraction technology was to add 8 volume of water to the culture and shaking in a vibrator at 37 ℃ for 1 h. It was shown that the crude enzyme can transform glutamine to glutamic acid.