The purification methods of bacterial protease have been published by many workers, especially by the using of ion exchange resins. But in the practical application to obtain a comparatively purified enzyme, the known methods do not give always a satisfiable results. Here we developed an industrially applicable method for purification of bacterial protease with the using of tannin. By the adaptation of the optimal conditions of this method on the purification, a 150000 unit/g.(Fuld Gross unit) of protease sample could obtained.