Abstract: In order to decrease the cost and improve the fish production of per unit water, a new method of water treatment with good purification results and a high loading rate needs to be selected. The results showed that supporting fish and hydraulic loading rate of fluidized bed biofilter is twice as high as those of fixed bed biofilter. The total ammonia N load of fluidized bed biofilter was 3 times higher than that of fixed bed biofilter and total ammonia N removal rate within effluent water total ammonia N mean values is 0.5 mg/L. The recirculation intensive fish culture system is convenient for operation and management, fish grow normally. The technology of fluidized bed biofilter could decrease the treatment apparatus and cost by 50%.