Abstract: Long-term excessive application of potassium sulfate not only causes soil acidification, nutrient imbalance and other problems, but also inhibits tobacco root growth and reduces tobacco leaf combustibility. Therefore, it is necessary to explore a suitable potassium fertilizer application scheme for local flue-cured tobacco production. Taking Yunyan 87, a main cultivated variety, as the test material, five gradient treatments of potassium carbonate replacing potassium sulfate were set up. The effects of different treatments on agronomic traits, economic traits, appearance quality, chemical components and sensory quality of flue-cured tobacco were systematically studied, and the optimal scheme was screened out by comprehensive index evaluation. Partial or total replacement of potassium sulfate with potassium carbonate had no significant effect on the agronomic and economic traits of flue-cured tobacco. Both single application of potassium sulfate（T1 treatment）and complete replacement of potassium sulfate with potassium carbonate（T5 treatment）had adverse effects on tobacco leaf quality, while partial replacement treatments significantly improved the quality. Among them, T2 treatment（potassium carbonate 41.25 kg·hm⁻² + potassium sulfate 168.75 kg·hm⁻²）showed the best coordination of chemical components and the highest sensory quality of tobacco leaves, with the highest comprehensive score. T2 treatment（potassium carbonate 41.25 kg·hm⁻² + potassium sulfate 168.75 kg·hm⁻²）can not only ensure sulfur supply, but also give play to the advantages of potassium carbonate, which can be used as the optimal potassium fertilizer application scheme for Yunyan 87 in Ji'an area.