Flue-cured tobacco cultivar K326 in China responds differently to nitrogen fertilizer rates. Excessive fertilizer can harm the environment. In experiments, higher nitrogen levels initially increased tobacco quality and price, but then decreased them. Inferior tobacco increased with higher nitrogen. Sugar content decreased, while nitrogen and nicotine increased. Best sensory scores were at 90-120 kg N/ha. Soil nitrate increased with nitrogen. The cultivar K326 responded best to 90 kg N/ha.