The invention relates to a biochemical simultaneous phosphorus and nitrogen removal method of domestic sewage. Sewage passes through a grating and a primary settling tank at first so that partial suspended solids are removed, next, the sewage passes through an anaerobic filter tank loaded with iron carbon filler and an aerobic filter tank, the effluent of the aerobic filter tank flows back to the anaerobic filter tank, organic matters in the sewage in the anaerobic state are acidified so that the pH is reduced, an electrochemical reaction is aroused on the surface layer of the iron carbon filler to intensify denitrification, and in the meantime, few ferrous ions (Fe<2+>) are dissolved out; the ferrous ions (Fe<2+>) are oxidized into ferric ions (Fe<3+>) in the aerobic state, the ferric ions react with soluble phosphate radicals in the sewage to generate precipitate, and finally, the sewage enters a sedimentation basin and is gravitationally settled, and then emitted. The biochemical simultaneous phosphorus and nitrogen removal method of domestic sewage, provided by the invention, has the advantages that no reagent needs to be fed independently to remove phosphorus, and only by virtue of the biochemical method, the COD (Chemical Oxygen Demand) in the yielding water is lower than 30 mg/L, TN (Total Nitrogen) in the yielding water is 1.5 mg/L and TP (Total Phosphorus) in the yielding water is 0.2 mg/L, and consequently, the yielding water is up to the class IV water standards of surface water. Furthermore, the biochemical simultaneous phosphorus and nitrogen removal method of domestic sewage is simple in process, and capable of saving investment and operation costs, and thus has a great application value.