A new long-chain glucoside was isolated from methanolic extract of Moringa oleifera leaves and identified as b-Dglucopyranosidetetradecanoate along with b-sitosterol and b-sitosterolglucoside. b-sitosterolglucoside was first report from this plant. Cytotoxicity bioassay against four human cancer lines was carried out. The compound exhibited good activity against colon cancer cell line (Colo-320 DM) with IC₉₀ value of 3.98. The compound showed moderate to low activity against other 3 cell lines (PA-1, MCF-7 and KB-403).