The objective of this review study is to shed light on the effective role played by nanotechnology, especially nanoparticles, in the medical field. We take nanoparticles of zinc, nanoparticles of magnesium, and nanoparticles of copper, as examples. The conventional methods of developing NPs are costly and produce very toxic product, so the need of hour is to reduce the risk of toxicity in the environment from the different chemicals used in the physical and chemical methods. The alternate approaches found to develop NPs is “green synthesis. The green synthesis of nanoparticles is a novel way to synthesize nanoparticles by using biological sources. It is gaining attention and attracted the scientists from different fields due to its simplicity, and environmentally-friendly nature. In green synthesis, we use many plants that can contribute to converting metals into the nanoform, such as the purslane plant, which converts zinc and copper into the nanoform, which contributes to increasing the potency and biological and pharmaceutical activity of the two metals, as well as the basil plant, which contributed to the conversion of magnesium. To magnesium oxide, which has great effectiveness and great influence in the medical field. Green synthesis could produce nano-sized materials that could be a solution to many pathological conditions, such as those related to inflammation or oxidative stress.