||Thirty samples of particulate matter less than 10 µm (PM10) were collected from five sampling sites surrounding Mae Moh Basin, Lampang Province. The PM10 samples were collected once a month between February to July 2015 using Mini volume air sampler. The 10 species of PAHs concentration including Fluoranthene (Flu), Pyrene (Pyr), Banz[a]anthracene (BaA), Chrysene (Chr), Benzo[b]fluoranthene (BbF), Benzo[k]fluoranthene (BkF), Benzo[a]pyrene (BaP), Dibenz[a,h]anthracene (DBA), Benzo[g,h,i]peryrene (BghiPe) and Indeno[1,2,3-cd]pyrene (IDP) were analyzed by High Performance Liquid Chromatography with fluorescence detection (HPLC-FL). The average recoveries of PAHs were found in the range of 93-107%. The 24 hours PM10 concentrations varied from 18.98 to 174.07 µg/m3. The total 10 species of PAHs concentration varied from 0.15 to 23.87 ng/m3. The characterization of PAHs in PM10 shows the predominant PAHs species in BghiPe, IDP, BaP and BbF respectively. In addition, the patterns of PAHs distribution in different number of benzene rings were significantly higher in 6-rings following by 5- and 4-rings respectively. In generally, the results indicated that the major sources of air pollution in this study are vehicle emission, biomass burning and coal combustion by different percentages.