Abstract: In view the catechin components determination, quality and ester catching proportion of the Sect. Thea tea trees in southwestern Guizhou Province, we used Sect. Thea tea trees natural resources in Anshun City, Liupanshui City, Xingyi City, Qianxinan State of Guizhou Province and‘Fudingdabaicha’tea trees as the test material and took the average differences analytic methods to analysis the 6 catechin components determination (EGC, DL-EC, EGCG, GCG, ECG). The results showed that the esterncatechines of Sect. Thea tea trees in Anshun City, Liupanshui City, Xingyi City, Qianxinan state were 81.55% , 41.10% , 83.13% , 77.03% , 82.85% , and the quality index were 5.39, 19.79, 7.84, 5.25, 6.65, respectively. Cluster analysis results showed that Sect. Thea tea tree in Xingyi City was similar to‘Fudingdabaicha’tea trees, while Sect. Thea tea tree in Anshun City was similar to Sect. Thea tea trees in Qianxinan state when the threshold value of Euclid distance were 0.9 to 3.2.