In view of the current problems existing in the production and application of artificial floating islands, such as complex process, high cost, bringing secondary pollution, limited materials and as well as the fact of the serious nitrogen and phosphorus pollution in the agricultural catchments areas, rice straw, bamboos, cinder and some other cheap or waste raw materials were used to make artificial floating islands for purifying the water in farmland catchments areas. The results showed that our artificial floating island owned the advantages of low cost, simple process and could avoid secondary pollution; when the coverage of artificial floating islands took 8% of total area of water, the purification rates of nitrogen and phosphorus were 60.1% and 54.9%, respectively; ryegrass was a more ideal floating-islands plant in winter; cinder was a more ideal matrix for plant cultivation.