Eight undescribed, along with five known steroidal alkaloids were isolated from Solanum nigrum L., a plant used in traditional Chinese medicine. Their structures were elucidated by NMR, HR-ESI-MS, and IR spectroscopy. Two compounds displayed an unusual structure in steroidal alkaloids with an open E-ring and without an F-ring present. To evaluate their bioactivities, nine compounds were selected to intervene five human cancer cell lines including H1299, HepG2, HeLa, HCT116, and MCF7 respectively. All compounds exhibited inhibitory effects for the five cell lines, revealing potential anti-tumor activities from Solanum nigrum. CI - Copyright (c) 2022. Published by Elsevier Ltd.