In allusion to the algal eutrophlcation problem of urban shallow lakes, four enclosures were set up in an urban eutrophic pond of Nanjing City to restore submerged macrophytes communities. Results showed that Eichhor-nia crassipes can be used to improve the transparency of water body, and its effect was relative to its coverage when its coverage was less than 0.3m. With the coverage no less than 0. 3 Eichhomia crassipes can make transparency improved from lower than 0.3m to higher than 0.6m during 30 to 40 days in summer. The submerged vegetation was availably restored after transparency improved to higher than 0.6m. Compared to the period without submerged vegetation,the transparency of the water body was enhanced 70% and Chi.a concentration were reduced 50% correspondingly.