With the advent in nanotechnology, the synthesis of green nanoparticles and its applications has been a crucial step of inception for sustainable agriculture. The synthesis of nanoparticles from biological resources paves a shift in burden from commercial and synthetic means of agriculture to economical and environment friendly methods. The application of nanomaterials from plant, micro-organisms and bio-waste based extracts has been shown to result positive with high biodegradability, enhanced functional role and less toxicity. The application of green metallic nanoparticles bio-fabricated with different biological extracts as nano-fertilizers, nano-pesticides and nano-biosensors are now widely tested in various aspects of horticulture and cultivation of crops in farming to address the problems of biotic and abiotic stresses. The lacuna to treat the pollutants by photo catalysis, disease control and efficient nutrient feed additive has been heavily tested by green metallic nanoparticles to enhance the habitat for better aquafarming and also in livestock rearing. The new age usage of bio synthesized nanoparticles in meat industry for enhanced shelf life and spoilage detection with intelligent nano-packaging opens the paradigm of areas for future. Thus, this chapter sheds light on the applications of green synthesized nanoparticles in different sectors of agriculture and their future prospects.