To provide a sterilized simple toilet which allows defecation in an existing container even when a toilet is unavailable due to suspension of water supply or breakage of a sewer, does not cause propagation of bacteria, and is storable/disposable in the open air.

A combined use toilet 6 where a toilet seat 4 with a defecation hole 3 opened is placed on the container opening edge 2 of an existing container 1 and a slip stopping material is attached to the rear side of the toiler seat 4. The bag opening part 8 of a toilet bag 7 loaded in the defecation hole 2 is attached to the container opening edge 2 or a toilet seat outer periphery 9. Inside the toilet bag 7, water absorbing powder 10, and excreta sterilizer 14 where one or more kind of degrading enzymes 11 such as cellulase, amylase, protease and lipase, are mixed with one or more kinds of irons 12 such as pure iron, ferrous sulfate, ferric sulfate, ferrous chloride and ferric chloride, and one or more kind of coppers 13 such as pure copper, cuprous oxide, or cupric oxide, are loaded at the same time. After defecation, the bag opening part 8 is hermetically sealed with a fastener or a solidly binding material 17, the toilet bag 7 is shaken and stirred to perform sterilization and prevent bad odor.