BACKGROUND: Researchers have searched for plant-derived medicines over the last few decades. Although much of the focus has been on medicinal herbs, many vegetables, such as sweetpotato, have also been discovered to have medicinal properties due to their high levels of nutrients and phytochemicals. This study aimed to determine the effects of methanolic extracts from sweetpotato leaves and leaves/stems on human lung (A549) and breast (BT549) cancer cell lines. The authors obtained the leafy greens from Tennessee State University's Organic research farm, extracted with methanol and studied for their cytotoxicity. METHODS: Alamar blue Assay was used to determine whether the methanolic extracts from fresh sweetpotato leaves (cv. All Purple) and leaves/stems (cv. Carolina Ruby) had the potential to affect cell proliferation in the human lung (A549) and breast (BT549) cell lines in-vitro. Tamoxifen was used as the positive control, while DMSO was used as the negative control. RESULTS: Sweetpotato leaves of the All-Purple cultivar and the stem/leaves of the Carolina Ruby cultivar inhibited lung and breast cancer cell growth in a dose-dependent manner. The All purple sweetpotato produced EC CONCLUSIONS: Anticancer activities of these extracts showed their ability to inhibit the growth of cancer cell lines, such as BT549 (breast cancer) and A549 (lung cancer), in a concentration-dependent manner. Further studies would help determine the bioactive compounds present in these compounds that produce this effect, but more studies would also help determine whether the extracts could induce apoptosis in BT549 and A549 cancer cells, the mechanism of action, and cell cycle progression.