Abstract: Under the background of global climate change and water scarcity, drought has become one of the major abiotic factors affecting crop growth and yield, thereby posing a serious threat to global food security. In recent years, nanoparticles have demonstrated significant potential for synergistically enhancing the drought resistance of crops due to their unique physicochemical properties. Therefore, this paper summarized the research results in recent years. It reviews the effects of drought stress on plant physiology, biochemistry and morphology, as well as the response strategies of plants. Drought stress has adverse effects on plant development, as well as on physiological and metabolic pathways, causing interference with cell membranes, antioxidant activity, photosynthetic systems and nutrient absorption, thereby affecting plant growth and crop productivity. In response, plants have evolved adaptive mechanisms such as drought escape, drought avoidance, and drought tolerance. The strategic application of nanoparticles under drought conditions can effectively bolster crop resilience, subsequently elevating yield and quality. The review systematically summarizes the regulatory mechanisms of nanoparticles on crop drought resistance. These mechanisms encompass reinforcing the antioxidant defense system, optimizing photosynthetic performance, facilitating osmotic adjustment, modulating hormonal balance and associated gene expression, and preserving nutrient homeostasis. At the same time, the influence of the properties of nanoparticles on the drought resistance of crops was discussed: in terms of the type of nanoparticles, ZnO NPs exhibited remarkable promoting growth effects under drought stress; in terms of the application concentration, the application concentration of NPs under drought conditions had a quadratic parabolic trend on the biomass of the aboveground parts of crops, with a decrease at low application concentrations and an increase at high application concentrations; in terms of the application method, foliar spraying and soil application of NPs were the most effective for crop growth under drought conditions. The article also pointed out the current application status and challenges of nanoparticles in alleviating drought stress. Future research on nanomaterials in the field of crop drought resistance can focus on issues such as the standardization of precise application, optimization of the composition of nanodesign components, deep-level signal regulation of drought response, integration of multi-omics and gene editing technologies to analyze mechanisms, and adaptability to multiple stresses. On the basis of eliminating the biological toxicity and environmental ecological risks of nanomaterials, it is necessary to promote the efficient and sustainable application of nanomaterials in agricultural drought resistance. The paper aims to explore the alleviation of crop drought stress mediated by nanoparticles, thereby providing theoretical guidance for the research and application of nano-fertilizers, and promoting sustainable agricultural development and ensuring global food security.