Green synthesis of metal nanoparticles (NPs) has attracted considerable attention because of its cheaper protocols and is more environmentally friendly than standard synthetic methods. In the present study, we report the green synthesis of zinc oxide nanoparticles (ZnO NPs) and copper oxide nanoparticles (CuO NPs) by using Caralluma tuberculata stem extract. ZnO NPs and CuO NPs were characterized by using UV–Visible Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDX). UV–Visible absorption data of ZnO NPs and CuO NPs showed the characteristic absorption peak at 380 nm and 460nm. FTIR analysis confirmed the capping of nanoparticles by phytochemicals present in Caralluma tuberculata, which showed absorption bands in the range of 3500-3000 cm-1 , 1700-1600 cm-1 , 1000 cm-1, and below 900 cm-1 . SEM revealed the morphological features of the synthesized ZnO NPs and CuO NPs with an average size of 40 nm and 60 nm, respectively. EDX spectroscopy of ZnO NPs shows two peaks of zinc at 1 keV and 8.5 keV, and a single peak for oxygen atoms at 0.5 keV. For CuO NPs two strong peaks of copper at 1keV and 8 keV, and a single peak for oxygen atom at 0.5 keV was observed, affirming the purity and successful synthesis of crystalline metal oxide nanoparticles. Synthesized ZnO NPs showed tremendous antibacterial activity against S. aureus and Acetobacter strains. CuO NPS showed significant activity against S. aureus, while moderate activity against Acetobacter. A Hybrid of ZnO NPs and CuO NPs showed considerable activity against both tested bacteria. The acetone extract was equally effective against both strains, while aqueous and mixed extract was more effective against S. Aureus than Acetobacter. Furthermore, the photocatalytic activity of ZnO NPs and CuO NPs was examined by degradation of xylene dye and congo red dye under UV light. ZnO NPs degraded 60% of xylene dye, while CuO NPs degraded 90% of Congo red dye in 30 minutes.