To provide a garbage disposer in which garbage is decomposed and made extinct by action of microorganisms.

The garbage disposer 1 consists of an agitation chamber 3 provided with an agitation means 4 like agitation blades 4b, a fungus bed 5 which is provided in the inside of the agitation chamber 3 and constituted of many granules 5a and microorganisms living in the fungus bed 5. Garbage A and the fungus bed 5 are agitated by the agitation means 4 in the agitation chamber 3 and garbage is decomposed by action of microorganisms. In this device 1, microorganisms function by agitating and mixing garbage A and the granules 5a and garbage A is decomposed into water, carbon dioxide and ammonia gas or the like and made extinct.