As part of ongoing research on development of standard extract from fruit hull of mangosteen (Garcinia mangostana Linn.) and application in pharmaceutical and cosmetic industry,D -mangostin was purified from the extract of mangosteen fruit hull. D -Mangostin exhibited high anti-proliferative activity against human colon cancer cells (HCT116 and HT29, at 80.0 % and 75.5 % inhibition, respectively) and human prostate cancer cell (PC3, at 78.5% inhibition). This result showed that mangosteen and D mangostin would be good candidate for therapeutic application for cancer treatment.