Garcinia xanthochymus is a tropical fruit yielding tree native to South East Asia.Its fruit is used to treat bilious conditions,diarrhea and dysentery.In this study,11 new polycyclic polyprenylated acylphloroglucinols (PPAPs) (1-11) and 21 known compounds including 9 phloroglucinols,7 xanthones and 5 flavonoids were isolated from fruits of G.xanthochymus.Their structures were elucidated by detailed spectroscopic analyses.All isolated compounds were evaluated anti-proliferative activities against four human tumor cells (HepG2,A549,SGC7901,MCF-7).As a result,PPAPs displayed potential inhibitory activity against four human cancer cell lines.These data suggested that the extracts of fruits of G.xanthochymus are potent candidates for cancer prevention.