Abstract: The benzob furan,quinoline,carbazole,9-methylcarbazole,dibenzoa,j acridine,dibenzoa,h acridine and 7H-dibenzoc,g carbazole in particulate matter of mainstream cigarette smoke of 6 brands were extracted with CH₂Cl₂ containing D₇-quinoline(internal standard),purified with a base alumina SPE column,and then determined by gas chromatography/mass spectrometry under selective ion detection model.The results indicated that:1) the recoveries of the heterocyclic aromatic hydrocarbons were in the range of 76.0% to 119.2% with the RSDs of less 3% except 9-methylcarbazole(8.21%),and the limits of detection were 0.04 to 0.43 ng/cig;2) the contents of benzob furan,quinoline,carbazole and 9-methylcarbazole basically agreed with those reported in references;3) dibenzoa,j acridine,dibenzoa,h acridine and 7H-dibenzc,g carbazole were not detectable;4) except 9-methylcarbazole,the benzobfuran,quinoline and carbazole in the smoke of 3 domestic Virginia type cigarettes were much higher than those in 2 reference cigarettes and one imported blended type cigarette.