A new C(17)-polyacetylene, named hederyne A (1), has been isolated from the MeOH extract of galls of Hedera rhombea Bean (Araliaceae), together with two known polyacetylenes, falcarindiol (2) and 11,12-dehydrofalcarinol (3). The structure elucidation of 1 was achieved by NMR, MS, IR, and UV