Objective To find a sustainable path towards green and low-carbon development the tobacco industry is actively searching for alternative heating energy sources to traditional coal and fossil fuels for curing tobacco leaves under the background of the ??dual carbon goals. However it is still unclear how different heating energy sources affect carbon emissions during the curing process in tobacco barns. Methods Using the carbon emission factor method and flue gas measurement method the study compares and analyzes the carbon dioxide CO2 emissions from four different energy sources coal biomass natural gas and electricity used for curing one batch of waist-level tobacco leaves in a barn. Results The carbon dioxide concentration in coal-fired barns is significantly higher than that in biomass-fired and natural gas-fired barns with the lowest concentration observed in natural gas-fired barns. The carbon dioxide emission factors per unit of product dry tobacco leaves rank from highest to lowest are coal-fired barns>biomass-fired barns>natural gas-fired barns>electric heating barns at 3. 31 1. 80 1. 34 and 0. 85 respectively. Replacing traditional coal with biomass energy can reduce carbon dioxide emissions by 45. 6% per unit of product. Conclusion Compared with traditional coal biomass energy in tobacco curing barns demonstrates a significant carbon emission reduction. These findings can promote green and sustainable development in China?? s tobacco industry and contribute to achieving the ??dual carbon goals on schedule.