The invention relates to a method for separating extraction and recycling of nitrogen and phosphorus ions in domestic sewage. The method mainly comprises the steps that: A) a half double-layer pipe is laid in a domestic sewage sewer pipeline, the middle of two walls of the half double-layer pipe is wrapped with a metal coil (plate), the two ends of which can be energized to form an electric field, and the nitrogen and phosphorus ions in domestic sewage are effected by the electric field in the pipeline so as to be separated from the liquid in the sewage; B) the separated nitrogen and phosphorus ions are added with a chemical reagent to form a precipitate able to serve as a fertilizer; and C) the nitrogen and phosphorus ion separated domestic sewage is used as a plant fertilizer. By utilizing the principle that charged ions in sewage can shift in the electric field, the invention realizes recovery and reuse of nitrogen and phosphorus substances such as nitrogen, phosphorus and potassium, etc. The system involved in the invention has the advantages of low building cost, simple construction, small land occupation, low running cost, simple maintenance and the like, and is in line withthe willingness of common people, thus having very high utility and popularization value.