Urban vegetation is an effective way to remove the particulate matter in atmosphere. More attention of the previous studies focuses on microscale such as single leaf scale; however, the studies on single tree scale are scarce, which is key to select greening trees and evaluate their environmental benefits. Pinus bungeana trees with different diameters at breast height (DBH) at three differently polluted sites in Beijing were selected as research materials. The captured amounts of particulates were measured at the single leaf and single tree scale through collecting particulates on leaf surface, investigating the leaf surface microstructure by Scanning Electron Microscopy (SEM), and measuring the leaf area of each sample. For P. bungeana, the maximum amounts of PM_2.5, PM₁₀ and TSP capture per unit leaf area were 0.15, 0.29 and 0.97 g·m^-2. The DBH had no significant effects on the amount of captured particulates per unit leaf area (P>0.05). Among the sample trees with different DBH, the stomatal size and density on leaves were consistent, the grooveshaped projection distribution was evenness, and there were no marked differences for distribution groovelike projections. DBH had a marked impact on particulates retention on the tree scale (P<0.05), and the DHB with high particulate matter capture centered on 12.7-25.5 cm. The maximum amounts of PM_2.5, PM₁₀ and TSP capture were 5.77, 12.88 and 43.08 g per single tree, respectively. The DBH of P. bungeana had little effect on the microstructure of leaves, but a significant effect on crown radius and leaf area index. Thus, the DHB showed no significant effects on particulate matter retention at single leaf scale, but a significant impact on particulate matter retention on the single tree scale.