The principles and methods of green synthesis have become pivotal in advancing sustainable chemistry, focusing on lowering environmental impact and enhancing the safety of chemical processes. Green synthesis encompasses a variety of techniques and methodologies that tightly align with the green chemistry principles, aiming to reduce toxicity, energy consumption, and waste production while maximizing efficiency and sustainability. This method minimizes toxicity while improving the biocompatibility of nanoparticles, rendering them ideal for an increasing range of applications, including environmental remediation and biomedical purposes. The chapter delves into green chemistry principles, the role of biosynthesis in enabling nanomaterials synthesis and its mechanisms, and the key bio sources of green synthesis; this analysis provides an overview of green synthesis and its mechanisms for further innovation in biosynthetic methodologies.