The antiproliferative constituents in the MeOH extracts of the aerial parts of Lippia dulcis Trev. and Lippia canescens Kunth (Verbenaceae) were investigated. Activity-guided chemical investigation of the MeOH extracts resulted in the isolation of the three bisabolane-type sesquiterpenes [(+)-hernandulcin (1), (-)-epihernandulcin (2), and (+)-anymol (3)] and four phenylethanoid glycosides [acteoside (4), isoacteoside (5), martynoside (6), and a new diacetylmartynoside (7)] from the former, and four phenylethanoid glycosides [acteoside (4), isoacteoside (5), arenarioside (8), and leucosceptoside A (9)] and three flavones [desmethoxycentaureidin (10), eupafolin (11), and 6-hydroxyluteolin (12)] from the latter. Antiproliferative activity of the isolated compounds against murine melanoma (B16F10), human gastric adenocarcinoma (MK-1), and human uterine carcinoma (HeLa) cells was estimated. (+)-Anymol (3), acteoside (4), isoacteoside (5), arenarioside (8), eupafolin (11), and 6-hydroxyluteolin (12) had GI50 values of 10-16 microM against B16F10 cell. Desmethoxycentaureidin (10) and eupafolin (11) showed high inhibitory activity against HeLa cell growth (GI50 9 microM, and 6 microM, respectively).