Epieriocalyxin A, a diterpenoid isolated from I. eriocalyx, suppressed Caco-2 colon cancer cell growth. Western blot results showed that both JNK and ERK1/2 activation was decreased after Epieriocalyxin A treatment in a dose-dependent manner. Epieriocalyxin A increased the expression of caspase 3 and Bax, and decreased Bcl2 expression. Our results suggest that Epieriocalyxin A is a novel compound that induces colon cancer apoptosis. Epieriocalyxin A could be a potential drug for colon cancer therapy in the future.