Abstract: Based on the field investigation of full-bodied type typical county (Xiangcheng, Xuancheng, Guiyang, Jianghua), about four counties and thirty seven sites, as well as clean aroma type county (Jiangchuan, Najian, Yongding, Taining), about four counties and thirty four sites, combining 1:500 000 geological map, the agro-geological background (geological time and parent rocks) of different aroma tobacco region were studied. The results showed that (1) the geological time span of full-bodied type and clean aroma type tobacco region was both large, the former covered Cenozoic Era, Mesozoic Era and Palaeozoic Era, including five periods, nine epochs, the latter covered Cenozoic Era, Mesozoic Era, Palaeozoic Era, Neoproterozoic Era and Mesoproterozoic Era, including ten periods, twelve epochs. (2)The differences between parent rocks of different aroma tobacco region were obvious. The Full-bodied type tobacco region mainly were composed of carbonate sedimentary rocks and loess, both of them had high content of calcium carbonates. The clean aroma type tobacco region were mainly composed of clastic rocks. Conclusively, geological time characteristic is not a major factor of leading tobacco flavor differentiation, parent rocks have obvious influence on the formation of tobacco scent types.