Abstract: Taking the negative ion concentration of water in Sun Island as the objects of study, [Objective][Method]Applying ArcGIS to interpolate the negative ion concentration of Solar Waterfall and Solar Lake in Sun Island, Harbin, and analyzed the distribution characteristics of negative ion concentration in different types of water bodies.[Objective]The correlation between the concentration of negative ion in the lake with temperature and humidity were studied.[Result] It was found that the negative ion concentration of the lake was positively correlated with the temperature and humidity,[Method]The optimal function model of negative ion concentration with temperature and humidity in the Sun Lake area were fitted by SPSS, and the significance test were carried out with the significance level of 0.01.[Objective][Method]The air cleanliness of Sun Waterfall, Sun Lake, Swan Lake and Wetland Garden in Sun Island Scenic Area were evaluated by means of air quality evaluation index.[Result]The evaluation result shows that the air cleanliness level of the Solar Waterfall, the Swan Lake and the Wetland Garden are Grade A, the air quality reach the cleanest standard, the air cleanliness level of the Sun Lake is Grade B, and the air quality has reached the standard of general cleaning,[Conclusion]which can be used as a reference for the study of air negative ions.