Rapid population expansion and environmental concerns in agriculture necessitate innovative and long-term solutions to fulfill the world’s increasing food demand. Recent nanotechnological breakthroughs have demonstrated extensive use in agricultural protection and postharvest. Engineered nanoparticles are critical for plant control, seed germination, and genetic modification. Nanoparticles might be used to distribute fertilizers, insecticides, herbicides, and plant growth regulators in a more focused and controlled manner. In the food industry, this improves crop growth and production capacity by reducing chemical-based pesticides and their water solubility, protecting agrochemicals from deterioration, enhancing soil health, and naturally controlling crop pathogens, weeds, and insects. Despite the potential benefits of nanomaterials, their full adoption in agriculture has yet to be realized, owing primarily to concerns about nanoparticle absorption, translocation, bioavailability, and ecotoxicity. Understanding the underlying mechanisms and reactions caused by nanoparticles using molecular techniques is crucial for evaluating nanomaterials’ biological potential. This chapter discusses nanoparticles’ role in enhancing plant development and soil fertility, managing plant diseases, and addressing plant and soil toxicity. It discusses nanotechnology’s potential to combat abiotic stress in crops, improve growth, absorption, and translocation, and highlights critical applications for sustainable agriculture and food systems, including stress management. The importance and significance of nanotechnology in addressing agricultural and food sector difficulties and concerns, as well as the limitations and future potential of nanoparticles, are critically explored.