To provide a granular substance treatment apparatus capable of outstandingly shortening a treatment time of the granular substance by making feeding of a treatment gas uniform.

The granular substance treatment apparatus 1 is provided with a vessel 2 and a treatment tank 3. The vessel 2 has a throwing port 9 for throwing the granular substance to the inside. The treatment tank 3 receives the granular substance thrown from the throwing port 9. The treatment tank 3 gets a shape thinner with downward advancement. At least a lower part of the treatment tank 3 is made of a material having a gas permeability for allowing passing of a treatment gas for treating the granular substance. The upper part of the treatment tank 3 has a smaller gas permeability than the lower part of the treatment tank 3.