Polycyclic aromatic hydrocarbons(PAHs) of 16 types were measured in sediment from Xidayang Reservoir, Hebei Prov-ince, and the possible sources and potential risk assessment also had been analyzed.Total PAHs concentrations varied from 422.36 to 1052.90 ng/g in surface sediment, and increased continuously from reservoir upstream to the front areas of the reservoir dam.The total PAHs concentrations ranged from 388.81 to 1205.56 ng/g in a sediment profile, and increased continuously from the bot-tom(20 cm under the surface) to the surface sediment.Naphthalene, Phenanthrene, Fluoranthene, Benzo(b) fluoranthene, Chrysene and Pyrene were dominant compounds of PAHs in the sediment.The total PAHs concentration was positively correlated to TOC contents with a correlation coefficient of 0.91 in surface sediment and 0.93 in profile sediment.TOC absorbs more strongly high molecular weight PAHs(HPAHs) than low molecular weight PAHs(LPAHs).The main source of PAHs was originated from com-bustions of fossil fuels and biomass.In general, PAHs pollution in sediment appeared to be moderate to low leveling in Xidayang Reser-voir.Risk assessment suggested that PAHs was no significant biological impairment, suggesting a low toxicological risk up to now.