PM10 (particulate matter which passes through a size selective impactor inlet with a 50% efficiency cut-off at 10 µm aerodynamic diameter) and PM2.5 were collected at four sites (A: Xiaoping, B: Huli, C: Hongwen, D: Gulang Island) from December 20, 2004 to December 29, 2004 in Xiamen. 16 Priority polycyclic aromatic hydrocarbons (PAHs) in PM10/PM2.5 were quantified by using a gas chromatograph/mass spectrometer (GC/MS). EC and OC of PM10 were analyzed by Thermal/Optical Carbon Analyzer (DRI Model 2001). Concentration, spatial distributions of PAHs and EC/OC were studied and their main sources were identified by diagnostic ratios, correlation analysis and EC/OC analysis. Among the different sampling sites, concentrations of Σ16PAHs were 5.20-28.07 ng/m3 in PM10 and 3.04-11.32 ng/m3 in PM2.5. Concentration of OC were 9.83-15.6 μg/m3 and 1.41-4.73 μg/m3 for EC associated to PM10. The main sources identified were traffic emissions and industry emission/coal combustion.