Abstract: The study aims to analyze the catechins components of different tea varieties, and explore the seasonal change rule of catechins components of 10 new materials of Yunnan large- leaf tea. The results showed that the components in tea catechins had a certain seasonal change law. The average content order of EC and EGC in spring, summer and autumn was autumn tea>summer tea> spring tea, that of ECG was autumn tea=summer tea>spring tea, and that of EGCG was summer tea>autumn tea>spring tea. In addition to the spring tea material 5 and 8(whose change rule of catechins components was EGCG> EGC> ECG> EC), the change trend of other materials was EGCG> ECG＞ EGC＞ EC, in addition to the summer tea material 3 (whose change rule was EGCG> EGC> ECG> EC), and material 6 (whose change rule was EGCG> ECG= EGC> EC), the change trend of other materials was EGCG> ECG＞ EGC＞EC, and the change trend of all the autumn tea materials was EGCG＞ EGC＞ ECG＞EC. For the 10 materials of the three seasons, the variation range of average content of EC, EGC, ECG and EGCG was 0.73%-1.83%, 1.96%-4.96%, 2.76%-3.22%, and 8.57%-9.57%, respectively. The overall change trend of various components was EGCG> ECG> EGC> EC. The quality average index of catechins material 7 of the three seasons was the highest, and that of material 6 was the lowest. Of the three seasons, summer tea had the highest quality index, followed by spring tea and then autumn tea. In general, among the 10 new materials of Yunnan large-leaf tea varieties selected, there is a significant difference in the content of catechins components among different seasons.