To study the chemical constituents from the n-BuOH extraction of Nauclea offcinalis xylem and their biological activities.The n-BuOH extraction of N. offcinalis were separated with silica gel,Sephadex LH-20 and other chromatographic materials.The isolates’ structures were identified by the analysis of NMR,MS and other physicochemical properties.And then,the pNPG and MTT methods were employed to evaluate their α-glucosidase inhibitory and tumor cell cytotoxicity activities,respectively.Fifteen compounds were isolated and identified as naucleaphenol A (1),4-O-β-D-(6-O-vanilloylglucopyranosyl)-vanillicacid (2),saccharumoside B (3),1-O-(vanillicacid)-6-(3′′,5′′-dimethoxygalloyl)-β-D-glucopyranoside (4),swerosid (5),phoenixoside A (6),medioresinol (7),rel-5-(1R,5S-dimethyl-3R,4R,8S-trihydroxy-oxa-6-oxobicyclo-［3,2,1］oct-8-yl)-3-methyl-2Z,4E-pentadienoic acid(8),3,4-dimethoxycinnamic acid (9),trans-cinnamic acid (10),3,4-dimethoxyphenyl-β-D-glucopyranoside (11),3,4,5-trimethoxyphenyl-β-D-glucopyranoside (12),p-hydroxybenzaldehyde (13),protocatechuic acid (14) and 1,3,5-trimethoxybenzene (15).Naucleaphenol A (1) is a new compound,and compounds 2-4,6-8 and 11 were isolated from N. offcinalis for the first time.The bioactivity result showed that compounds 3,7,8,11 and 13 presented weak α-glucosidase inhibitory activities,while all the compounds showed no cytotoxicity at the test concentration.