The present study aimed to explain the influence of novel SnO2/Calcite bio-nano composite on HepG2 cell line, and its antioxidant, and antimicrobial properties. In this study, green fabrication of SnO2/Calcite bio-nano composite was synthesized based on cypress leaves and eggshell wastes, characterized structurally by SEM, TEM, XRD, EDAX, elemental analysis, and FT-IR for more information about this composite. We study the cytotoxic potential of SnO2/Calcite bio-nano composite against human liver cancer HepG2 cell line. In vitro free radical scavenging, total antioxidant capacity, and antimicrobial activity of this bio-nano composite were investigated. SnO2/Calcite bio-nano composite was displayed anti-cancer, antioxidant, and antimicrobial properties successfully. Also, the results suggest that SnO2/Calcite bio-nano composite holds more significant potential than calcite and SnO2 nanoparticles against bacteria and fungi. These results displayed that SnO2/Calcite bio-nano composite might be used for the design of novel anti-proliferative and antimicrobial bioagents.