Previously, the occurrence of (-)kaur-16-en-19-oic acid(1)l)and a new diterpenic acid, (-)pimara-8( 14), 15-dien-19-oic acid(ll) in the roots of Aralia cordata(Japanese name: Udo) and A. racemosa was reported 2). The present paper deals with the further study on the related diterpenes of Aralia spp. It has been found that the stems and the leaves of the above plants also contain I and If. From the acidic fraction of the ether-extract of the roots of ~. cordata, the following compounds have now been obtained as.minor constituents3): Acid A C~H~2 04, mp 260-262~ /U/D -85.0"(pyridine), IR~KBrmax 3365 and 1696cm -I. Acid B C20H30 03, mp 292-294"(decomp), /a/D -70.4"(pyridine, lHYmaxKBr 3360 and 1697cm -I. Acid C C2oH2803, mp 241-245~ /~/D -54.2"(pyridine), IR~KBrmax 1717, 1699, and 1667cm -I. KBr Acid D C2oH3oO3, mp 218~ %~'/D -62.8"(pyridine), IR ~max 3480 and 1680cm -I. Acid A was proved to be identical with 16,17.dihydroxy-!6~-(-)kauran-19-oic acid(lll), which was already isolated from Beyeria spp 4}. CCI. Acid B(IV) afforded an oily methyl ester(V), /~/D -64"5"(CHC13)' IR ~max 4 3625 and 1730cm ~I. As shown in Table I, the NMR spectra of IV and V indicated the presence of a trisubstituted double bond and a vinyl group. In the NMR spectra determined for CDCI 3 solution as well as for pyridine-d 5 solution, three tertiary methyl signals of IV and V appeared at the almost same positions as those of II and its methyl ester(VI), respectively 2)." These results and the co-occurrence of II in the same plant led to suggest that acid B(IV) would be an analogue of II