The invention belongs to the technical field of biological pharmacy, in particular to a fermenting device for biological pharmacy. To solve the problems of complicated structure and large noise in theuse process of the fermenting device, the fermenting device adopts the scheme that the fermenting device comprises a fermenting box, wherein an air ventilating hole is formed in the inner wall of thebottom part of the fermenting box; the inner wall of the air ventilating hole is connected with a protective net through a bolt; the outer wall of the bottom part of the fermenting box is connected with a heating box through a bolt; the interior of a casing of the heating box is provided with an installation groove; a heat isolation plate is inserted into the installation groove; the inner wall of the corresponding side of the heating box is connected with a heating wire installation base through a bolt. The fermenting device has the advantages that the noise produced in the working process of a first air pump and a water pump is effectively isolated by a sound isolation plate; in the use process, only a second air pump produces noise, so that the noise in the working process is effectively reduced, the fermenting effect of microorganisms in the fermenting box is effectively improved, and the environment in the fermenting box is more suitable for the fermenting of the microorganisms.