Crops are exposed to several abiotic stresses among which floods are the second largest disaster causing high economic losses in crop and livestock production. Flooding, submerging, and waterlogging cause hypoxia in plants leading to many physiological processes that activate plant defense mechanism to fight the induced stress. Prolonged exposure can lead to death of plants causing an alarming situation. Climatic change can worsen this situation and hence, there is a need to design such practices that can help the plants to tolerate stress so that the effects of these abiotic factors can be tackled. Nanotechnology have played a revolutionary role in agriculture, and the nanoparticles particularly of metal and metal oxides owing to their easy synthetic route and availability of raw materials are a deemed useful and cost-effective solution to multiple agro-problems. In this regard, various nanoparticles have been used that have impacted the plant biomass, photosynthetic activity, antioxidant activity, generation of metabolites, osmolytes, enzymes, etc., that can enhance the plant tolerance to fight against stress. The response of plant to these nanoparticles varies with particle size, dosage, mode of application, type of nanoparticle, plant varieties, etc. The chapter presents a bird’s eye-view related to different stresses the plants are exposed to as a result of over-watering and the role of metal-based NPs in mitigating the stress in plants thereby increasing their yield.