Sewage treatment tank

The utility model relates to the technical field of sewage treatment, in particular to a sewage treatment tank which comprises a sludge pump, an anaerobic tank, an anoxic tank and an aerobic tank, the anaerobic tank, the anoxic tank and the aerobic tank are sequentially communicated, an inclined tube settling tank is fixed on the inner upper portion of the anaerobic tank and communicated with the aerobic tank, and an inlet end of the sludge pump is communicated with the bottom of the inclined tube settling tank. The outlet end of the sludge pump is communicated with the anaerobic tank, and the inclined tube settling tank is positioned at the upper part in the anaerobic tank, so that the distance between the inclined tube settling tank and the anaerobic tank is shortened, the activated sludge at the bottom of the inclined tube settling tank can be pumped out of the anaerobic tank by using the small-function sludge pump, and the energy consumption of the sludge pump during conveying of the activated sludge is r