The study looked at how different amounts of nitrogen, phosphorus, and potassium fertilizers affect the yield and profit of filling flue-cured tobacco. They found that using more phosphorus and potassium fertilizers increased the tobacco yield, while using more nitrogen fertilizer decreased it. The best economic benefit came from using nitrogen fertilizer. The recommended fertilization rates for tobacco production in the Songhua River basin are 39.0-51.0 kg/ha of nitrogen, 44.4-67.0 kg/ha of phosphorus, and 91.7-137.5 kg/ha of potassium.