In order to improve the economic benefits of Carya illinoinensis planting, this experiment took 4-year-old fruit trees as the research object, based on the "3414" optimized fertilization program, to study the effects of nitrogen, phosphorus and potassium ratios on the role of the target forest trees, the distribution of the law. The results showed that: the synergistic effect of nitrogen and phosphorus is the key, which restricts the distribution of nitrogen, phosphorus and potassium in the kernels and leaves, of which the effect of nitrogen is more obvious, followed by phosphorus , and the recommended treatment of 14,5 and 6 was the optimal fertilization scheme, that is, 804 g of urea, 362-724 g of diamine phosphate and 320-640 g of potassium sulfate were applied per Carya illinoinensis,which not only promotes the tree's healthy and sustainable growth and development, but also significantly improves the economic benefits of the growers, which has certain popularization value in actual production.