Abstract: Seven-year-old Pinus koraiensis from a Hegang clone nut orchard was used as the experimental material to determine the contents of chlorophyll, soluble sugar and endogenous hormones during the fertilization experiment of N, P and K from June 2019 to mid-June in the 2021, the effects of fertilization on physiology and endogenous hormones of Pinus koraiensis clones were studied. The results showed that the contents of chlorophyll a, chlorophyll b and total chlorophyll of Pinus koraiensis clones were significantly increased by fertilization, and the contents of N and P fertilizer were the highest, which were 39.55%, 14.68% and 28.52% higher than those of the control, respectively. The response of chlorophyll content of different clones to fertilization was different. The chlorophyll content of HG18, HG16, HG9 was significantly higher than that of control after N, P application. After fertilization, ABA（Abscisic acid） content was significantly higher than that of the control, and N fertilizer treatment increased by 152.2%, while GA₃（Gibberellic acid 3） and IAA（Indole aceticacid） contents were significantly lower than that of the control. The response of GA₃, IAA and ABA contents of different clones to fertilization was different, the GA₃ and IAA contents of HG50 and HG40 were significantly increased after fertilization, while the ABA contents of HG25 and HG24 were significantly increased. After fertilization, chlorophyll content was negatively correlated with GAs（Gibberellic acids content） and positively correlated with ABA, while soluble sugar content was positively correlated with GA₃. In conclusion, fertilization increased ABA content and decreased GA₃ and IAA content, which had an effect on increasing chlorophyll content and decreasing soluble sugar accumulation in plants.