By constructed different modes of wetland systems, this paper investigated their purification efficiencies and persistence influenced, singly and in combination, by substrates made up and plant grown on. The results showed that the purification efficiency of wetland be increased by growing plant, and were higher in substrate mixed by sand and soil than substrate made of scree. The purification efficiencies of wetlands grown mixture of Cyperus alternifolius and Canna indica, and mixture of Cyperus alternifolius,Canna indica and Phragmites communis are higher than that of wetland grown Cyperus alternifolius singly. Small size substrate and mixture of plants are able to stable the purification efficiencies of wetlands.