To provide an improved garbage treatment process for converting a large amount of garbage which is food leftovers discharged from a kitchen of a hotel, general restaurant, traditional Japanese restaurant or the like, into a fertilizer.

This garbage treatment process comprises: a grinding stage for grinding garbage to be treated; a dehydration stage for dehydrating the ground garbage; a fermentation accelerator addition/mixing stage for adding and mixing a fermentation accelerator into the crushed and dehydrated garbage; an air-blowing fermentation/agitation stage for fermenting the garbage containing the fermentation accelerator while agitating it by air blowing, (primary fermentation); a fermentation/agitation stage for fermenting the primary- fermented garbage while agitating it, (secondary fermentation); a particle-size- uniformizing agitation stage for uniformizing the particle size of the secondary- fermented garbage by agitating it; and a foreign matter screening/removal stage for screening and removing foreign matters from the resulting garbage. The fermentation accelerator comprises ground rice hull, rice straw, large-saw dust, rice bran and a mineral solution.