Tetrastigma hemsleyanum Diels et Gilg(TDG),a family member of Vitaceae,is a popular traditional Chinese medicine and functional food.In the present study,the individual phenolic compounds were characterized by using UPLC-QTOF-MS/MS.A total of 23 phenolics were identified in TDG(13 in leaf and 10 in root).The antioxidant activities of several extractions(extracted by 80%methanol,ethyl acetate and hexane,respectively)obtained from the leaf and root of TDG were investigated and compared.It showed that the leaf extracted by 80%methanol extract exhibited the highest antioxidant activities(DPPH: 3.32 mmol trolox/g DW,ABTS: 1.38 mmol trolox/g DW,FRAP: 1.85 mmol FeSO4/g DW),while the root extracted by hexane was the lowest(0.94,0.41 and 0.12,respectively).The total phenolic contents(TPC)of various extracts of TDG leaf and root ranged from 28.95 to 275.71 mg GAE/g DW and 9.53 to 121.60 mg GAE/g DW.Also,the antioxidant activities evaluated by DPPH,FRAP and ABTS assays correlated well with TPC.Due to the strong antioxidant activities,the antiproliferative activities of TDG leaf and root were investigated.Results showed that 80%methanol extracts(leaf and root)provided good antiproliferative activities on HepG2 cells(IC50 = 524 and 539 μg/mL).Then,the 80%methanol extracts were extracted again by petroleum ether,chloroform,ethyl acetate and n-butanol to find out the possible bioactive compounds.The effects of these fractions(extracted by petroleum ether,chloroform,ethyl acetate and n-butanol)on HepG2 cell growth were evaluated.Finally,ethyl acetate fractions(leaf and root)showed the highest antiproliferative activities(IC50 = 8.27 and 12.64 μg/mL).Ten of the phenolic compounds were bioactive compounds and showed antiproliferative activity.This paper provides a complete profile of phenolics in TDG as well as their antioxidant and antiproliferative activities.