To provide a spreader for the spores of microorganisms used mainly in the koji-making process in the brewing industry.

This spore spreader has such a scheme that the discharge port 2 of a hopper 1 holding spores is furnished with a screw 9 for quantitatively extruding the spores via the port 2 downward so as not to project the lower terminal end of the screw 9 into a distribution tube 13 connected with the discharge port 2, and the spores are carried while blowing air into the distribution tube 13.