Sewage treatment system

The invention relates to a sewage treatment system. The sewage treatment system is applicable to treatment and purification of various kinds of sewage and muddy water, so that water can be recycled, water resources can be saved, and the environment can be protected. The sewage treatment system comprises an adjusting tank, a No.1 reaction tank, an air floatation tank, a No.2 reaction tank, a filtering tank, a sedimentation tank, a reuse water box, a filter press and a water storage tank, wherein a water outlet of the adjusting tank is communicated with a water inlet of the filter press; a water outlet of the filter press is communicated with a water inlet of the water storage tank; a water outlet of the water storage tank is communicated with a water inlet of the No.1 reaction tank; a water outlet of the No.1 reaction tank is communicated with a water inlet of the air floatation tank; a water outlet of the air floatation tank is communicated with a water inlet of the No.2 reaction tank; a water outlet of the filtering tank is communicated with a water inlet of the sedimentation tank; a water outlet of the sedimentation tank is communicated with a water inlet of the reuse water box; bottoms of both the filtering tank and the sedimentation tank are communicated with the water inlet of the filter press.