Abstract: How to evaluate the restoration effect of lakes is the difficulty of ecological restoration. By analyzing the relationship among nutrient concentration, water quality, comprehensive trophic level index TLI(Σ) and nitrogen isotope ratios(δ15N) of different organic matter in urban lakes with different restoration states in Wuhan, the feasibility of using the δ15N values of a certain organic matter in water to indicate the water pollution state of urban lakes, and then as an evaluation index of restoration effect was studied. As the result revealed, the water quality of South Lake, East Lake and inner Shahu Lake was below class Ⅴ, Ⅳ and Ⅲ respectively; the eutrophication degree was severe eutrophication, light eutrophication and mesotrophication respectively. The average δ15N value of organic matter in South Lake was 13.193‰(8.394‰~19.380‰) and the highest,  followed by the East Lake of 8.191‰(5.162‰~13.488‰) and the inner Shahu Lake of 2.940‰(0.001‰ ~6.433‰) in the lowest place. The δ15N values of organic matter in different lakes were positively correlated with the concentration of total nitrogen(TN), dissolved inorganic nitrogen(DIN), ammonia nitrogen(NH4+-N), total phosphorus(TP), water quality and TLI(), among which, the correlation among the δ15N value of suspended organic matter, δ15N value of submerged macrophyte and water pollution parameters was the most significant, these all could effectively characterize the water pollution state of urban lakes. For the convenience of sampling and the generality of the samples, it is suggested that the δ15N of suspended organic matter should be used as a rapid evaluation index for the water pollution state and the effect of water environment treatment.