Abstract:A new diterpene, rabdocoetsin D (1) was isolated from the ethereal extract of the leaves of Rabdosia coetsa (Buch-Ham, ex, D. Don) Hara (Labiatae) collected in Sichuan, China. Its strueture was established as lα, 7β-dihydroxy-llβ-acetoxy-ent-7β, 20-epoxy-kaur-16-en-15-one by spectroscopic and chemical evidence. Three known diterpenoids, rabdocoetsin B and C, rosthorin A were also isolated.