<p>Among tumors, liver cancer has an inferior prognosis. Therefore, exploring alternative strategies to improve the effectiveness of&#xa0;treatment for this ailment&#xa0;is of utmost urgency. In this study, we focused on analyzing the anti-cancer properties of bacterial exopolysaccharide from <i>Bacillus velezensis</i> associated with the&#xa0;seaweed <i>Sargassum wightii</i> against hepatocellular adenocarcinoma. A culture-dependent method was used to isolate heterotrophic <i>B. velezensis,</i> which was then&#xa0;evaluated for its antioxidant and anti-cancer properties. A <i>β</i>-(1 → 3) linked sulfated polygalactan exopolysaccharide (BVEP-2) was isolated from the bacterial extract and characterized by spectroscopic analysis. The anti-cancer property was analyzed through assays involving 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), neutral red uptake (NRU), and apoptosis (by annexin V-FITC/PI staining) against the&#xa0;human hepatocellular adenocarcinoma cell line (HepG2). BVEP-2 demonstrated potential cytotoxicity in the MTT assay (IC₅₀ 65.05 μg/mL) and 23.02% cell viability in the&#xa0;NRU assay at a 100&#xa0;µg/mL concentration of BVEP-2 against HepG2, compared to the standard doxorubicin. Potential antioxidant properties of BVEP-2 (IC₅₀ 112–117 µg/mL) corroborated the anti-cancer activities, and the attenuation of free radicals could play a significant role in its&#xa0;anti-cancer potential. BVEP-2 induced approximately 9% early apoptosis and 39% late apoptosis in the HepG2 cell line, whereas the standard drug resulted in around 38%&#xa0;early apoptosis and 37% late apoptosis, along with 6% necrotic cells.&#xa0;The <i>β</i>-(1 → 3) linked sulfated polygalactan exopolysaccharide (BVEP-2) of <i>B. velezensis</i> MTCC13097 showed potential antioxidant and anti-cancer activities, and thus, could be developed as a promising pharmacophore lead against human hepatocellular adenocarcinoma.</p> Graphical Abstract <p></p>