The invention discloses a composition able to treat cancer. The composition contains a novel combination of triterpene compounds. The novel triterpene compound combination at least comprises ganoderic acid S (GAS), ganoderic acid T (GAT), ganoderic acid Me (GAMe), ganoderic acid R (GAR), and ganodermic acid S (GMAS). The disclosed composition can be used for treatment or prophylaxis of rectal cancer, liver cancer, breast cancer, lung cancer or leukemia.