Abstract: To understand the effects of combined application of N and P on the stoichiometric characteristics of N, P and K in different organs（root, stem, leaf and sprout） of Pinus yunnanensis seedlings, the seasonal variation characteristics of the stoichiometric ratio of ω（N）∶ω（P）, ω（N）∶ω（K） and ω（P）∶ω（K） in different organs（root, stem, leaf and sprout） of P. yunnanensis seedlings were analyzed, and the seedlings of P.yunnanensis treated with different N and P were sampled and measured, and different fertilization experiments were carried out by using 3×3 regression design with 2 factors and 3 levels of N and P. The effects of combined application of N and P on the stoichiometric ratio of N, P and K in roots, leaves, stems and sprouts of P. yunnanensis after stumping were studied. The results showed that P. yunnanensis seedlings had no rule for the distribution of nutrient elements in different organs after flat stubble, but showed rich variation. With the change of fertilization season, ω（N）∶ω（P） decreased gradually in roots, stems and sprouts, and decreased first and then increased in leaves, but the overall difference was not significant. There were some differences in the effects of single application of N, P and combined application of N and P on the growth of P. yunnanensis seedlings. In general, the combined application of N and P was more beneficial to promote the growth of seedlings, and treatment No.5（N₁P₁） showed extremely significant（P＜0.01）. The N, P and K stoichiometric ratios of all organs of seedlings were mainly influenced by the N×P interaction, followed by N and P was the least. The positive and negative correlations between ω（N）∶ω（P） and ω（N）∶ω（K） remained unchanged except in roots and leaves were changed, where the correlation between ω（N）∶ω（P） and ω（N）∶ω（K）. The correlations between ω（N）∶ω（P） and ω（P）∶ω（K）, ω（N）∶ω（K） and ω（P）∶ω（K） changed with seasonal changes in fertilizer application and the correlation coefficients decreased, regulated by P and K, respectively.Stumping changed the content of nutrient elements in the plant, and different fertilization treatments made significant differences in the stoichiometric characteristics of N, P and K in different organs of P. yunnanensis（P＜0.01）. The combined application of N and P could effectively alleviate the limiting effect of single application of N and P on plants, and the nutrients was in a balanced state, and meet the needs of plant growth.