Abstract: For better utilization of tobacco stalks and clean tobacco production in fields, the physical and chemical properties of flue-cured tobacco stalks carbonized at different temperatures were studied. The results showed that the yield of tobacco stalk carbonization reduced with a rise in temperature. The total carbon content in carbonized stalk was slightly affected in low temperature carbonization, however it declined as the temperature rose to 300℃and above. Carbonate ions and inorganic carbon content was very low in low temperature carbonization, which increased obviously once temperature reached up to 400℃. In low temperature carbonization, the p H of tobacco-stalk-biochar presented weak acid, p H value rosesteadily and turned alkaline from 300 to 800℃. The cation exchange capacity(CEC) of tobacco-stalk-biochar increased first, then dropped with a rise in temperature, and peaked at 400℃. With a rise in carbonization temperature, the alkaline functional groups increased, while acidic functional groups reduced on the surface of tobacco-stalk-biochar. Tobacco-stalk-biochar was of porous structure. The appropriate carbonization temperature for flue-cured tobacco stalks is 400-500℃.