A flush toilet of the present invention has a toilet stool and an incinerating pot, they are connected to each other by a vertical drain pipe. A shutter is provided which opens the drain pipe during discharge of waste material and closes after completion of the discharge. The shutter is positioned approximately midway of the drain pipe. Raw sewage can be delivered to the incinerating pot, and flush water can be introduced to another location. By introducing flush water to another location, only raw sewage or other waste material can be efficiently incinerated. The flush water used can be reused as flush water after filtration with a filtering apparatus.