Source characterization techniques for accumulated particulates and ambient particulates are presented. Polycyclic aromatic hydrocarbons(PAHs) profiles and physical form were used in qualitative and quantitative source apportionment estimations. Using gas chromatography and gas chromatography-mass spectrometry, PAHs and oxygenated derivatives of FAH were measured in the ten particulate samples which were collected from tailpipes of vehicles, freeway tunnel, rural area, indoor air and sintering furnace. The standard reference material (SRM) 1649 and 1650 were also analyzed. Total PAH contents from PAH fraction of freeway tunnel, diesel truck, coal powder, SRM1650 and diesel engine extracts were dominated by the low molecular-weight PAHs such as phenanthrene, fluoranthene, pyrene, benz(a)anthracene and chrysene/triphenylene. Oxygenated PAHs were predominant in the moderately polar fractions of accumulated particulates collected from vehicular tailpipes and freeway tunnel. Similar PAH concentration profiles by ring size were observed between similar source groups. The ten particulate samples were statistically classified in three groups : the vehicle traffic group I(freeway tunnel, diesel truck, SRM1650, coal powder and diesel engine), ambient aerosol group ii (gasoline engine, rural area, indoor air and SRM1649), industry related group III (sintering furnace). Characteristic ratios of PAHs to benzo(e)pyrene (BeP) from the particulates were measured and compared to the published data. Ratios of PAHs to BeP from the group I or those from the group II were within the range of those from other tunnel and automobile studies or those from aerosol studies, respectively.