Water treatment equipment for recirculating aquaculture contains: at least one aquaculture tank, an aeration unit, at least one water circulating tank, a plurality of membrane filtering units and a water returning unit. Each aquaculture tank includes plural connecting plate units and a flowing cup； the aeration unit includes a plurality of air supply pipes. Each water circulating tank includes a nitration reacting chamber and an accommodating chamber, and the nitration reacting chamber has a flow tube outwardly extending to the flowing cup and a nitrifying bacteria layer fixed therein. Each membrane filtering unit is a circularly flat membrane and includes a water pipe and plural disc-shaped film bags, wherein each film bag has two filtering films communicating with the water pipe； and the water returning unit is fixed outside each aquaculture tank and includes a pump and a water return tube.
