Steviol and five new diterpenes have been isolated from the outer layer of the root bark of Bruguiera gymnorhiza Lam of the Andaman and Nicobar Islands. They are ent-kaur-15-en-19-hydroxy-16-al, 14(S)-isopimar-7-en-14,15-diol, ent-kaur-15-en-19,16-diol, methyl-ent-kaur-6(17)-en-19,12-epoxy-15-hydroxy-16-oate, 16β,14(R)-ent-pimar-8(14)-en-1,14,15-triol. Their structures were established by means of spectral studies, chemical reactions and, in case of the last compound, by X-ray analysis.