Abstract: To investigate the effects of different nitrogen, phosphorus, and potassium fertilizer application rates on the agronomic traits of flue-cured tobacco and the occurrence of cutworms, and to select the optimal fertilization scheme that balances superior tobacco agronomic traits with effective cutworm control, providing a theoretical basis for scientific fertilization in plateau tobacco regions. In 2025, a field experiment was conducted in Ninglang County（elevation 2161 m）of Lijiang City using Yunyan 99 as the test variety. A three-factor, five-level second-order orthogonal regression design was employed, with 17 treatments and three replications. Measurements included plant height, leaf number, maximum leaf length, maximum leaf width, and cutworm occurrence index. A second-order polynomial regression model was established, and the optimal fertilization scheme was selected using the 95% confidence interval superposition method. Different fertilization treatments significantly influenced all measured indicators（P＜0.05). Treatment T9 exhibited the highest plant height（119.87 cm), T11 showed the greatest leaf number（18 leaves), T6 achieved the maximum leaf length（65.43 cm）and leaf width（35.17 cm), while T5 demonstrated the lowest cutworm occurrence index（1.28). The regression model had correlation coefficients（R）ranging from 0.8350 to 0.9693, indicating high fitting accuracy. Plant height was primarily affected by nitrogen and phosphorus fertilizers, leaf number responded most strongly to potassium fertilizer, while maximum leaf length and width required coordinated nitrogen, phosphorus, and potassium inputs. The cutworm occurrence index was most closely related to nitrogen fertilizer application. Based on a comprehensive 95% confidence interval superposition analysis of all indicators, the optimal fertilization scheme balancing superior tobacco agronomic traits and effective cutworm control was determined to be 96.75 kg·hm⁻²of nitrogen fertilizer, 84 kg·hm⁻² of phosphorus fertilizer, and 157.5 kg·hm⁻² of potassium fertilizer.