Background : This study was carried out to investigate the cytotoxicity in 9 extracts from 8 medicinal plants, such as leaf extract of Lonicera maackii (Llm), leaf extract of Platycarya strobilacea (Lps), flower extract of Fagopyrum dibortryis (Fdf), stem extract of Physostegia virginiana (Spv), root extract of Allium senescence (Ras), aerial part extract of Allium schoenoprasum (Aas), aerial part extract of Artemisia japonica var. manshurica (Aaj), stem extract of Caryopteris incana (Sci), and leaf extract of Caryopteris incana (Lci), on human cancer cell lines. Methods and Results : Dried plant extracts were granted from National Institute of Horticultural and Herbal Sciences. The extracts of each plant were dissolved in DMSO and stored in deep freeze at –20℃. The cell viabilities were examined by MTT assay. On SK-OV-3 cell line, Lps, Aas, Sci ans Lci showed dose-dependent cytotoxic effect. On A549 cell line, almost samples show dose-dependent cytotoxic effect, but especially Aaj showed relatively high cytotoxic effect. In case of HCT-15 cell line, Llm and Aas showed relatively high cytotoxic effect. Conclusion : These results suggested that Lonicera maackii, Platycarya strobilacea, Fagopyrum dibortryis, Physostegia virginiana, Allium senescence, Allium schoenoprasum, Artemisia japonica var. manshurica, and Caryopteris incana can be utilized as potential sources of anticancer agent due to their cytotoxicity.