Objective: Curcuma longa is a known natural medicine for inflammation from ancient times. It has a low absorption rate and poor solubility. Hence, it is used for the green synthesis of nanoparticles. Zinc oxide nanoparticle (ZnO NPs) is famous nanoparticles which are economical, less toxic, and brilliantly biocompatible. They have potential biomedical properties, mainly anticancer, antidiabetic, and antimicrobial.Methods: The present study was designed to investigate in vitro analysis of the antimicrobial activity against pathogenic bacteria and fungi and its ability to scavenge reactive oxygen radicals of ZnO NPs.Results and Conclusion: The results indicated that ZnO NPs produced from C. longa had higher antimicrobial activity against Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, and Candida albicans. Therefore, we suggest that ZnO NPs can be used as the antimicrobial agent. It is a good scavenger of superoxide radical, nitric oxide, and hydrogen peroxide and has reducing power, which is greater than ascorbic acid at a higher concentration.