To provide a system for treating organic waste capable of preventing the work environment and the natural environment from being impaired and reducing a treatment cost reutilizing the treated organic waste.

The organic waste A is subjected to a fermentation treatment by a waster fermentation chamber 41 and is separated to produced flammable gas G and the organic waste A subjected to the fermentation treatment. The flammable gas G is fed to a hot air feeding device 53 to be subjected to approximately complete burning and the hot air H heated by the heat generated at the time of the burning is fed into a drying drum 52 of a waste drying device 50. The organic waste A subjected to the fermentation treatment is fed into the drying drum 52 of the waste drying device 50 and is stirred and a moisture content contained in the organic waste A is adsorbed/separated by the hot air H fed into the drying drum 52 to dry it to a predetermined moisture content. Thereby, a carbonized waste Aa dried/treated to the approximately carbonized state is manufactured.