Integrating nanotechnology into the current agricultural landscape can enhance plants’ resilience to stress and increase their productivity during unpredictable climatic scenarios. Nanoproducts, including nanopesticides and nanofertilizers, have been introduced to foster sustainable agriculture. This chapter aims to summarize the positive effects of aluminum oxide nanoparticles (Al2O3 NPs) on the morphological, physiological, biochemical and genotypic alteration of different plant species under stressful conditions. In most of the studies, aluminium nanoparticles accelerated the plant growth and yield, and in some cases, they even boosted plant defenses against abiotic stress by regulating the production of secondary metabolites, antioxidant systems and by regulating the expression of multiple stress-responsive genes. When used at optimal levels, they enhance biotic stress tolerance by triggering genotoxicity and reactive oxygen species (ROS) bursts in pathogens. However, these nanoparticles can have negative effects on the crop plants and soil microflora, which must be avoided. Hence, further research is necessary to develop new formulations that can be directly applied to crops for stress priming without compromising crop biosafety.