By a solid-state culture of raw barley with fermented Bacillus natto BN-1 , a thrombolytic enzyme, nattokinase, could be produced. Nattokinase production reached its maximum level after 1 day of fermentation at 37°C, and then gradually decreased. However, in the presence of a high concentration (0.5-2.0 M) of urea, the production level was increased and continued for a longer time. Bacillus natto fermentation was also possible when using raw wheat. The final product had very strong nattokinase thrombolytic activity as well as amidolytic activity for S-7388. During the fermentation, concentrations of vitamin K, (menaquinone-7; about 6.80 mg/100 g dry weight) and free amino acids, such as Phe and Lys, were increased. A much higher increase of GABA concentration-40 times more than that the before Bacillus natto treatment-was also confirmed.