Abstract: The polyphenols and antioxidant activities of different mango cultivars were studied. Polyphenols from four commercial mango (Ivory, Yu, Zihua and Sannian) mango kernels were extracted, determined and analyzed statistically. The results showed that mango kernel contained abundant polyphenolic compounds and had good antioxidant activity. Among them, the content of polyphenol in Zihua mango kernel was the highest and its antioxidant activity was the strongest, followed by Ivory mango kernel and Sannian mango kernel, and that in Yu mango kernel was the worst. There were great differences in the extracts of mango kernels among the four cultivars, which were easy to distinguish, and there was a positive correlation between the determination indexes. Among them, total phenols and hydrolyzed tannins were significantly correlated with in vitro antioxidant activities (P<0.05). Compounds in mango kernel were identified by UPLC-Tripe TOF-MS/MS, and 28 polyphenols and their derivatives were identified, including 2 phenolic acids, 8 phenolic esters, 10 phenolic glycosides, 7 flavonoid glycosides and 1 flavonoid. The results can provide scientific basis for reasonable selection of mango cultivars to extract polyphenols from mango kernel.