PURPOSE: To treat swine manure waste water so as to meet the conditions for environmental conservation and economical efficiency by subjecting swine dung to anaerobic fermentation and activated sludge aerobic degradation and effectively taking out microorganisms.

CONSTITUTION: A raw waste water basin 1 communicates with the drain ditches of a swine raising farm B1 and collects the excrement, washing water, etc., of the swine. This raw waste water basin 1 is internally provided with a mixing and agitating device 11. The waste water in the raw waste water basin 1 is sent through the inside of a pulverizing pipe 21 into a grit basin 2 by a blower A2. The waste water of the swine manure injected after the pulverization flows over from the upper part of the grit basin 2 and advances into a detached inlet from the bottom of a fermentation basin 3. The waste water discharged after the sepn. of solid from the liquid by the anaerobic fermentation in the fermentation basin 3 flows into a regulating reservoir 4. This regulating reservoir 4 adjusts the volume of the water flowing into an aeration basin 5. The waste water is then sent into the aeration basin 5. The waste water reacts with the aerobic activated sludge B3 therein and produces a mixture composed of the cleaned reaction water and the activated sludge B3. This mixture flows through an overflow port into a settling basin 6.