A sewage reuse system distributes a plurality of reuse water supply sections, each including a water introducing opening formed in a sewer trunk line; a treated sewage tank for storing reuse water; and a water level sensor for measuring a water level of the treated sewage tank, in a demand area of reuse water along the sewer trunk line. The system includes a movable sewage treatment section which moves to any of the plurality of water introducing openings; performs the sewage treatment to generate reuse water; and supplies the generated reuse water to the treated sewage tank, a communication section which transmits the water level data measured by the water level sensor, and a central control section which controls a water storing quantity of the treated sewage tank on the basis of the demand information of reuse water and the water level data.