The invention discloses a sewage treatment technique, belonging to the technical field of sewage treatment. The technique comprises the steps of: collecting sewage and leading the sewage to enter an adjusting tank to be evenly mixed; then, leading the mixed sewage to enter into an electric flocculation tank for electric flocculation; after electric flocculation, leading water body to pass through a sedimentation tank, and leading sludge precipitated inside the sedimentation tank to enter into a plate frame filter pressing system; leading supernate of the sedimentation tank to enter into an immersed ultra-filter tank, returning ultra-filter concentrated water into the adjusting tank, and leading the ultra-filter produced water to enter a reverse osmosis system; returning part of reverse osmosis concentrated water into the adjusting tank, and discharging the rest reverse osmosis concentrated water outside; and recycling reverse osmosis produced water which meets the recycling standard. The technique combines the electric flocculation technology and membrane separation technology, thus achieving the aims of improving the quality of the produced water and the recycling rate of the sewage.