The present invention provides a Z-shaped gas stripping reflux two-stage precipitation integrated sewage treatment tank, wherein the rectangular tank body contains a grid-containing sand settling pretreatment zone, an anoxic zone, an aeration zone, a clarifying reflux zone, an inclined pipe / plate precipitation zone, a contact disinfection ditch, and the like, and conventional water treatment equipment, a horizontal slit-type gas-water separator, a Z-shaped separation wall, a surface type gas stripping micro power reflux device arranged in a horizontal and completely-paving manner, and an L-shaped hydropower hybrid spiral flow generator are arranged inside the tank body. The Z-shaped gas stripping reflux two-stage precipitation integrated sewage treatment tank has a simple and compact structure, and has the following advantages that: denitrogenation, phosphorus removing, two stage precipitation and disinfection treatment are completed in the same tank; and compared with the conventional process adopting a plurality of independent small tanks, the Z-shaped gas stripping reflux two-stage precipitation integrated sewage treatment tank of the present invention has advantages of low investment, small occupation area, less agent consumption, less sludge discharge, low energy consumption, low cost, stable and controllable water quality, easy operation and management, and the like, and is especially suitable for sewage denitrogenation and phosphorus removing integrated treatments with a scale of 10000 tons / day and below.