Abstract: In order to identify the status of the aromatic substances of flue-tobacco,the difference on the contents among different tobacco-planting area and the ecological reasons,the relationship of petroleum ether extract contents between the varieties and different region from 12 tobacco-pant cities and 5 major cultural flue-tobacco varieties in Yunnan province was studied.The results showed that ① There was difference in petroleum ether extract contents among tobacco-producing areas,the contents ranged from 3.370 to 7.340 percent.Zhaotong tobacco-producing area possessed the highest content which reached 5.971 percent,and Qujing tobacco leaves had the lowest content as 4.888 percent.② K326 had the highest and Yunyan 97 had the lowest contents of petroleum ether extract,there was no significant difference among the 5 flue-tobacco varieties.③ The content of petroleum ether extract was related with the regional ecological factors such as the total sunshine duration,soil pH value and soil Cl-contents et al.,the coefficient of determination of fitted curve showed significantly difference.