To understand the role of underlying surface in affecting the pollution characteristics of polycyclic aromatic hydrocarbons( PAHs) in urban runoff,we analyzed the PAHs contents in runoff samples from different underlying surfaces in 4 rainfall events. In the study,the PAHs contents in runoff from roof(site A) and highway( site C) were much higher than other underlying surfaces,and their concentrations were up to 26. 66 and 27. 87 μg·L-1,respectively. PAH concentrations decreased along with rainfall duration...