Abstract: Eight pieces of samples are selected as the research object so as to study the influence for PM2.5 particles which green space in spring and its surrounding environment have exerted in Hangzhou city. Each sample was set five sampling points for PM2.5 data collection, and a survey is conducted on plant community structure, canopy density and its surrounding environment. The result indicates that concentration of PM2.5 is inversely proportional to the distance of pollution. City green space, especially arbor-shrub-lawn type of city green space with high canopy density, has a positive effect on the reduction of PM2.5. The water surface and pavement, as the disturbing environmental factors, make the reduction of PM2.5 particles less evident and stable. Under the different air quality level, there exist obvious differences in the reduction of PM2.5.