Abstract: 【Objective】In this paper, changes in leaf nutrients and their response to fertilization at different growth stages of Sapindus mukorossi Gaertn. under different fertilization treatments were revealed. Accordingly, the effects of different levels of nitrogen, phosphorus and potassium fertilizer on the yield were determined and the optimal fertilization formula was explored. The findings will support the optimization of rational fertilization technology for S. mukorossi Gaertn. 【Method】This paper used the “3414” random area group design method to conduct the experiment and determine the formula for fertilization. The effects of 14 treatments, including dynamic changes in the nutrient content and yield of the leaves of S. mukorossi Gaertn., were determined. 【Result】The N content in the leaves of S. mukorossi Gaertn. was significantly reduced during the inflorescence period(from April 15th to May 10th)and the period of fruit expansion(from June 25th to September 1st). The P content in the leaves of S. mukorossi Gaertn. was significantly reduced during the flowering period(from May 10th to June 10th)and the fruit expansion period(from June 25th to September 1st). The K content in the leaves of S. mukorossi Gaertn. showed a continuously declining trend from flowering(April 15th)until the end of fruit expansion(September 1st). The content of N, P and K increased with the addition of fertilizer, and N fertilizer and P fertilizer had synergistic effects. The trend in the yield of S. mukorossi Gaertn. increased and then decreased with increasing amounts of nitrogen, phosphorus and potassium fertilizer. The N2(600 kg/hm²)P2(300 kg/hm²)K2(500 kg/hm²)treatment had the optimal effects among all samples. The output was up to 2 254.28 kg/hm². Compared with CK, output significantly increased by 49.5%. 【Conclusion】 S. mukorossi Gaertn. with fertilization management in pumping should focus on nitrogen and potash fertilizer. Attention should be paid to the application of phosphorus and potassium fertilizer during the florescence period. Attention should also be paid to the application of the three kinds of fertilizer, including nitrogen, phosphorus and potassium, during the fruit enlargement period. It is suggested that the amount of fertilization should better be: N fertilizer 773 kg/hm², P fertilizer 273 kg/hm², and K fertilizer 557 kg/hm².