Abstract: The removal efficiency of the horizontal and vertical subsurface constructed wetlands with various combinations of substrates and aquatic plants and nitrogen and phosphorus from the slightly-polluted water body in the Xiangmu lake was investigated as a pilot experiments at the Tiexinqiao Water Experimental Center of Nanjing Hydraulic Research Institute. The analysis and testing results show that when the total nitrogen concentration in inflowing water is 0.793-2.662 mg/L, the average concentration of the total nitrogen in the vertical subsurface constructed wetland unit (unit 20) with cobblestone, gravel, coarse sand, find sand as the substrates and acoruscalamus as vegetation is the lowest, reaching 0.905; the average removal rate of the total nitrogen is the highest, up to 80.89%, 43.06% and 46.32% respectively during the testing periods, and the total nitrogen concentration in the outflow is reduced and the water quality is improved from the 5th category to the 3rd category. The mean total nitrogen concentration of the effluent from unit 20 is also 0.905 mg/L, which is lower than the 3nd of national water quality standard (GB3838—2002). When the influent phosphorus concentrations was 0.035-1.003 mg/L, the average total phosphorus removal rate of unit 20 was the highest, reaching 30.59%. Cheap gravel could obtain a relatively high phosphorus removal rate. The typical combination of aquatic plant and substrates in unit 20 can be applied to the nitrogen and phosphorus removal from the slightly polluted surface water body.