Abstract: Fume particales from vegetable oil with 270± 5℃ heating wer collected and extracted by acetone. The single cell gelelect rophoresis assay was applied to detect the occurrence of DN Asingle strand breaks intypeⅡ cell of rat lung after exposed to vegetable oil fume. The results showed the extent of DNA strand breaks in exposure group was singnificantly higher than that in control group. A correlation was found between tail length and vegetable oil fume exposure dosage(r=0.957, P< 0.05).These results are important to explore the genotoxicity and the role of lung cell as target tissue of cooking oil rume.