This machine adopts pump pressured mixture system that can absorb water and air at the same time, diamter of micro bubble produced by it it about 20-50um thus pressure pump, air compressor, jet device and dissolved air vessel are unnecessary. With auto-adjustable dissolved air system for gas-liquid seqaration tank, its stable performance for "one-minute" debugging ensures frequently swith without being readjusted. It is applicable for treating suspended particales, coagulation floccus and oil-water separation for municipal, paper making, chemical engineering, beverage production, printing and textile, oil refining, electroplating, food processing, slaughtering and leather industry.