An analytical runoff water quality model is developed for simulating polycyclic aromatic hydrocarbon (PAH) loading and transport via road runoff in an urban area. The model considers buildup and washoff processes of suspended solids in storm runoff and considers dissolved and particle-bound PAHs. Pollutant deposition and removal processes, which have typically been treated with a constant rate in previous models, are depicted as functions of relative humidity and wind speed to reflect the influence of meteorological conditions and are integrated into the pollutant buildup function. Pollutant input via rainwater and canopy throughfall from roadside trees is considered in the washoff model. The model is calibrated and verified with field data from an urban catchment in Beijing, China. The verification indicates that the runoff model is capable of providing results in good agreement with field measurements. A Monte Carlo framework is used to evaluate the uncertainty of PAH loading under various scenarios of atmospheric conditions.