Plant leaves play significant role for improving the quality of urban environment by acting as biological filters to capture atmospheric particulate matter.In this paper,the captured amount of TSP(total suspended particles) and PM_2.5(particles with diameter≤2.5 μm) per unit leaf area for 20 plants commonly used for urban greening in Beijing were measured by water washing methods,and the micro-structure of leaf surface of these plants were investigated by scanning electron microscopy.The mechanism that micro-structure of leaves surface how to affect the ability of capturing atmospheric particulate was discussed,through analyzing removal TSP and PM_2.5 numbers of 20 kinds of road plant with different surface micro-structure.The results showed:(1)There is significant difference in the captured amount of TSP and PM_2.5 per unit leaf area among the plant species,with the variation ranges of 0.40～3.44 g/m²(TSP) and 0.04～0.39 g/m²(PM_2.5),respectively.(2)The difference in groove width on leaf surface may be the main reason for explaining the difference of TSP and PM_2.5 retention among plant species;the grooves too broad and too narrow are not beneficial to trap particulate matter.The captured amount of PM_2.5 on leaf surface increases with increasing groove depth.(3)There are higher particle retention numbers for that plant with more stoma per unit leaf.The results have illustrated that captured amounts of TSP and PM_2.5 per unit leaf area on shrubs and lianas are greater than that on trees;leaf surface trench width of PM_2.5 holdup at around 5 μm larger;sycamore(Platanus acerifolia),hibiscus(Hibiscus syriacus) and Euonymus(Buxus sinica) unit leaf area stranded TSP and PM_2.5 amount compared with other test plants are larger.