In the context of escalating climate threats around the world, there is a growing need to develop new strategies to increase plants' stress resistance. Innovative approaches in this direction are provided by nanotechnologies that ensure the production of various nanomaterials (NMs). These include structures lessthan 100 nm in size that have unique physical and chemical properties. Due to this, NMs are able to penetrate biological barriers and accumulate in plant cells. The effects of NMs on a plant organism can be either positive or negative, depending on the chemical nature, sizes and concentrations of NMs, the object of study, and envi-ronmental conditions. Many NMs in a certain concentration are able to regulate almost all processes in a plant organism: growth, water metabolism, activity of the photosynthetic apparatus, and pro-/antioxidant balance.This suggests the possibility of using some NMs as adaptogens that enhance plants' stress resistance. This review presents a comparative analysis of experimental data on the use of NMs in plant physiology and agriculture to protect plants from the effects of unfavorable low and high temperatures. Possible mechanisms of NM action onplants are discussed as well as a strategy for their further use in fundamental science and agriculture.