There is a need for advanced developments to battle aggressive breast cancer variations and to address treatment resistance. In cancer therapy, ZnO nanoparticles (NPs) possess the ability to selectively and effectively induce apoptosis in cancer cells. There is an urgent necessity to create novel anti-cancer therapies, and recent studies indicate that ZnO nanoparticles have significant promise. The purpose of our study based on developed a simple, green synthesis method for ZnO-NPs nanoparticles using Hammada scoparia (Pomel) Iljin extract. Characterization through XRD, SEM, and FTIR confirmed the successful synthesis and structural properties of the NPs, revealing an average crystallite size of 17.786 nm and a particle size of 36.12 ± 4.52 nm. EDX analysis detected significant amounts of zinc and oxygen, while FTIR spectra identified various functional groups. Antioxidant assays (ABTS, DPPH, FRAP) showed that ZnO-NPs exhibit notable free radical scavenging activities, albeit less effective than ascorbic acid. Additionally, cyclic voltammetry and electronic spectroscopy studies indicated strong electrostatic interactions between ZnO-NPs and biomolecules such as DNA and BSA, suggesting potential applications in drug delivery. Cytotoxicity tests on MCF-7 breast cancer cells demonstrated significant dose-dependent inhibition of cell viability, emphasizing the potential of ZnO-NPs as effective agents in cancer therapy. Overall, the findings underscore the promising biomedical applications of ZnO-NPs, particularly in antioxidant and anticancer therapies.