Glinus oppositifolius L., a member of the Molluginaceae family, has a long-standing history of utilization as both a vegetable and a medicinal agent across numerous countries. This plant possesses a diverse range of pharmacological activities and attracts scientific interest in studying its chemical profile. The present phytochemical investigation of the plant resulted in the isolation of eleven new triterpenoid saponins, accompanied by three known compounds. Their structures were elucidated by intensive spectroscopic analysis, DFT calculations, and comparison with previously reported data. The isolates were evaluated for their anti-adipogenic effect and cytotoxicity against human cancer cell lines, namely, colorectal carcinoma HCT116, hepatoblastoma cell HepG2, breast cancer cell MDA-MB-231, and human lung adenocarcinoma cell A549. Compounds 5, 7, and 13 exhibited a potent inhibitory effect against the differentiation of preadipocyte 3T3-L1. In addition, compound 13 displayed inhibitory effects against the growth of A549 cancer cells.