Three new triterpenoid derivatives, 3-O-β-D-glucopyranosyl-20(S)-protopanaxtriol (1), 3-formyloxy-20-O-β-D-glucopyranosyl-20(S)-protopanaxtriol (2) and 26-hydroxyl-24(E)-20(S)-protopanaxtriol (3), along with six known ginsenosides, were isolated from leaves of Panax ginseng. Their structures were established on the basis of spectral analysis (IR, 1D and 2D NMR, HRESI-MS). Compounds 1-3 exhibited various degree of cytotoxicity towards human A549 pulmonary carcinoma cells and Hep3B hepatoma cells.