In this work, Annona muricata L. extract was used to synthesize ZnO-CuO bimetallic nanoparticles (NPs). We used UV-visible, FT-IR, XRD, XPS, FESEM-EDX, TEM, and Raman spectroscopy for analyzing ZnO-CuO NPs. The FESEM showed spherical ZnO-CuO. ZnO-CuO morphology was examined using TEM. ZnO-CuO crystalline planes are seen by XRD. The antibacterial, antioxidant, biocompatibility, and anticancer characteristics of green synthesized ZnO-CuO NPs were examined. The MTT experiment evaluated the produced bimetallic nanoparticles' inhibition of breast cancer (MCF-7) cell proliferation. The antibacterial activity of ZnO-CuO NPs was determined utilizing growth inhibition, ROS production, and live and dead cell tests. ZnO-CuO NPs showed superior bacteria-fighting ability at 100 mu g/mL. ZnO-CuO NPs also exhibit strong in vitro anticancer activity against MCF-7 cells. The MTT experiment showed a dose-dependent impact on MCF-7 cell lines, with an IC50 of 25 mu g/mL. The antioxidant activities of ZnO-CuO NPs depended on dosage, suggesting their potential as antioxidants. In fibroblast cells, ZnO-CuO NPs were tested for biocompatibility. Researchers found that NPs at greater concentrations (100 mu g/mL) did not harm cells, showing strong biocompatibility. Results demonstrated that green ZnO-CuO NPs may be antibacterial, antioxidant, and anticancer.