Disclosed are a membrane coupled activated sludge method and apparatus operating anoxic/anaerobic processes alternately for removal of nitrogen and phosporus, wherein nitrogen and phosphorous together with organics in the sewage, wastewater, filthy water etc. can be simultaneously removed with an economic and efficient manner, an operation thereof is easy and efficient, a capacity thereof is high and the method is economic due to the reduced operating costs with performing measurement and control of a recycle rate, a recycle time of alternate operation of the anoxic and anaerobic process, an amount of sludge, an amount of aeration and an operation of a blower for an intermittent membrane cleaning.