Objectives: The current work concentrated on the characterization of , Dodonaea Viscosa extract, investigations into its antibacterial properties, and the synthesis of copper oxide nanoparticles (CuO NPs). Methods: Under ideal circumstances (pH=11), 1 mM copper(II) sulfate pentahydrate was combined with 2% (m/v) aqueous , Dodonaea Viscosa extract of Dodonaea viscosa to create the CuO NPs. Results: The color shift from colorless to light yellow and finally to brownish has been used to first confirm the formation of CuO NPs. The kinetics of the reaction were examined with a UV-Visible spectrophotometer, revealing surface plasmon resonance at 382 nm. The calculated values of zeta potential and particle size were −15.2 mV and 197 nm, respectively. Gram-positive and gram-negative cultures were used to test CuO NPs' antibacterial activity, and the results demonstrate desirable activity. Conclusion: The study's conclusion shows that Dodonaea Viscosa extract converts Cu2+ metallic ions into CuO NPs by acting as a reducing and stabilizing agent. Following a successful green synthesis of the CuO NPs using Dodonaea Viscosa extract, the antibacterial activity, characterization, and activity against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria were examined.