An extensive discussion about green-synthesized nanomaterials and agricultural applications appears in this chapter and confronts the current requirement for sustainable farming practices. Four primary nanomaterial groups, including metal-based materials and carbon-based materials and polymer-based materials, and hybrid nanomaterials, show different characteristics for agricultural system applications. The plant growth enhancement and pest control and soil remediation capabilities of nanomaterials are exemplified through silver, gold, zinc, and iron among the metal-based category. Graphene and carbon nanotubes from the carbon-based materials family demonstrate excellent capabilities to enhance fertilizer performance as well as water management. Using polymer nanomaterials enables advanced methods to regulate agrochemical and soil amendment releases, yet hybrid nanomaterials produce several beneficial agricultural effects. Bio-based method synthesis represents a vital topic in this chapter because it uses plant extracts and microbial reducing and capping agents to produce environmentally beneficial and cost-effective products as alternatives to standard synthesis procedures. Numerous obstacles continue to affect the commercial development of nanomaterials in agriculture due to their safety constraints, alongside technological restrictions for industrial manufacturing and unclear regulations and high financial requirements for market uptake. This chapter examines how such materials should evolve to create smart nutrient systems and advanced crop defense methods and stress control systems as well as precision farming applications. Nanomaterials show promise to transform agricultural practices through better and sustainable farming methods and precise control mechanisms. The thorough study delivers vital information that helps scientists and agricultural experts and regulators in their mission to establish sustainable agricultural methods using nanotechnology.