In order to clarify the effects of different preceding crops on tobacco-planting soil and yield and quality of flue-cured tobacco, a field experiment was conducted with winter fallow as the control to study the effects of seven preceding crops, including radish, corn, tartary buckwheat, wheat, barley, green manure, and highland barley, on soil nutrients, agronomic and economic traits of flue-cured tobacco, chemical composition, and sensory quality of tobacco leaves. The results showed that: 1) Compared with the winter fallow treatment, green manure and highland barley increased soil pH by 0.02 and 0.12 units, respectively. Radish and corn increased soil hydrolyzable nitrogen content by 26.63% and 32.06%, respectively. Barley and highland barley increased soil available potassium content by 6.64% and 4.44%, respectively. All previous cropping increased soil available phosphorus content. 2) There were significant differences in agronomic and economic traits of tobacco under different pre-planting treatments. Maize significantly increased the number of effective leaves. Radish, maize, and tartary buckwheat significantly increased plant height of tobacco. Green manure increased the yield and the proportion of superior tobacco leaves. Wheat, barley, and highland barley increased the output value of tobacco leaves by 17.03%, 14.11%, and 3.99%, respectively. 3) There were significant differences in the chemical components of tobacco leaves under different pre-treatments. Green manure significantly increased total sugar and reducing sugar contents in the upper leaves by 11.77% and 12.27%, respectively. Wheat and barley significantly increased potassium content in the upper leaves by 30.43% ~ 53.91%. Radish and highland barley significantly increased sugar content by 37.55% - 67.66% in middle and lower leaves, respectively. Maize, barley, wheat, and highland barley significantly increased potassium content in the middle leaves by 5.80% ~ 28.40%. Meanwhile, radish and highland barley were beneficial to improve sweet aroma, increase aroma quality and quantity, and reduce the irritation and offensive odor of leaves. Comprehensive considering soil nutrient characteristics, agronomic and economic traits of tobacco, chemical composition, and sensory quality of tobacco leaves under different preceding crops, highland barley is recommended for the study area, which can increase soil available phosphorus and potassium contents, tobacco yield and output value, sugar and potassium content, and sensory evaluation quality of tobacco leaves.