<p>Engineered nanoparticles (ENPs) have emerged as a promising tool for enhancing plant resilience to abiotic stresses, offering innovative solutions for modern agriculture. This review provides a comprehensive analysis of the mechanisms by which metal-based, carbon-based, and polymeric NPs function under stress conditions such as drought, heat, and salinity. It examines how NPs influence key physiological processes, including osmotic regulation, antioxidant defense, and ion homeostasis, thus promoting plant growth and stress tolerance. Additionally, the review explores the synergistic effects of NPs across multiple abiotic stresses, as well as the potential of novel NP formulations, such as hybrid systems, which offer controlled release to maximize their benefits. Unlike earlier studies that mainly focused on the role of NPs in improving nutrient uptake and biomass production, this review broadens the scope by examining how ENPs can optimize photosynthetic efficiency and plant growth by enhancing chlorophyll content, improving light absorption, and stimulating beneficial soil microbial activity. As climate change poses increasing challenges to global food security, nanotechnology offers a sustainable approach to enhancing crop resilience and productivity. The review concludes by emphasizing the need for more research on the ecological impacts and long-term potential of ENPs in agricultural applications, highlighting their role in sustainable agriculture.</p>