Marine snails of the genus Conus are known for their complex venom compositions, containing a rich diversity of pharmacologically active peptides, collectively termed conotoxins. These peptides have garnered significant interest for their potential therapeutic applications, particularly in the realm of oncology. This study investigated the cytotoxic effects of venom gland and venom tube extracts from Conus virgo on three human cancer cell lines: Mcf7 (breast cancer), HepG2 (hepatocellular carcinoma), and Caco2 (colorectal cancer). Employing an in-vitro assay, we determined the half-maximal inhibitory concentrations (IC₅₀) of the venoms, which reflected their potency in reducing cell viability. The results demonstrated that both of the venom extracts exerted significant cytotoxic effects across all tested cell lines, with IC₅₀ values ranging from 173.89 to 481.27µg/ ml. The venom tube extract showed a consistently higher potency compared to the gland extract, suggesting a higher concentration of active cytotoxic compounds. The lowest IC₅₀ value was observed in the Mcf7 cell line when treated with venom tube extract, indicating a promising potential for breast cancer therapeutics. These findings supported the hypothesis that Conus virgo venom contained bioactive components with selective toxicity toward cancer cells. The consistency and reliability of the cytotoxic effects were substantiated by the narrow standard deviations obtained. This study contributed to the exploration of marine natural products as a source of novel anti-cancer agents. Additionally, it set the groundwork for future purification and mechanistic studies of conotoxins.