Numerous biotic and abiotic factors adversely influence agricultural crops, affecting plant growth and lowering crop yield. In order to make crop production systems sustainable in the face of biotic and abiotic constraints, technological innovation must be paired with efficient strategies. Using nanoparticles (NPs), nanofibres, nanoemulsions, and nanocapsules, nanobiotechnology offers an entirely novel set of tools to manipulate and improve crop yield. The application of nanoparticle-based smart delivery systems and nanosensors offers the potential for site-targeted delivery of different macromolecules required for enhanced plant defense, effective nutrient utilization, and disease resistance in an environmentally friendly way, as well as controlled release of agrochemicals. Nanomaterials like mesoporous silica particles (MSNs), gold nanoparticles (AuNPs), CNTs, and layer double hydroxides (LDHs) have recently come to light as highly effective and species-independent vectors for delivering genome engineering tools (DNA, RNA, proteins, and RNPs) to plants. By elevating anti-stress substances and triggering the expression of defense-related genes, the NPs can also upregulate the expression of genes related to stress. Given its great efficiency, affordability, environmental friendliness, and versatility in producing either transient or stable transformations in various plant species, nanoparticle-mediated gene delivery technology offers a technological advantage over conventional procedures. This chapter highlights advancements in nanobiotechnology and its role in promoting plant development and improving plant tolerance to biotic and abiotic stressors, as well as the underlying mechanisms.