Nanoscience and nanotechnology, particularly metallic nanostructures, have recently gained prominence owing to their widespread practical applications in almost every sector like healthcare, medical devices, agriculture and environmental products. The traditional methods involve physical and chemical processes for the synthesis of nanoparticles using synthetic chemicals. The recent innovation and adoption of new technologies have sparked a new movement known as the green chemistry, which reveals the significance of bioactive components present in the plants for the green synthesis of nanostructures and appears to have unmistakably highlighted the synthesis of homogenous, stable, and safe nanoparticles. An essential area of nanobiotechnology is developing around creating environmentally acceptable processes for synthesizing metal nanoparticles using plant-mediated strategies. Green synthesis strategies for metal nanoparticles have gained attention owing to their simple, reliable, cost-effective, non-toxic by-products with precise size, shape, and content control for large scale synthesis. Plant parts like leaves, roots, latex, seeds, and stems contain essential phytochemicals such as polyphenols, flavonoids, terpenoids, and others that synthesize metal nanoparticles. By adjusting the concentration of plant extract, pH, temperature, and metal salt ratio in the reaction medium, it is possible to control the size and shape of nanoparticles. This review will discuss the phyto-assisted synthesis of metallic nanoparticles, the variables affecting their synthesis, and their applications, which are summarized in this paper. Thus, this review will provide insight into the design and fabrication of nanostructures using plant-based resources, which could enable the discovery of new chemical entities for long-term and safer practical applications.