Abstract:From the leaves of Rabdosia macrocalyx(Dunn) Hara form (Labiatae), three new diterpenoids, macrocalyxoformin B, C and E, were isolated together with oleanolic acid, β-sitosterol and daucosterol. Their structures were established as (1), (3) and (7) by spectroscopic and chemical evidence respectively. Macrocalyxoformin B and C were shown to have inhibitory action on Hela cells, Staphylococcus aureus in vitro.