The influence of hardening (33 and 37°C) and damaging (43°C) temperatures on thermotolerance of cells of leaves and Hsp gene expression were studied on seedlings wheat. It was shown, that thermotolerance of plant cells under 33 and 37°Cgradually rose and reached to a maximum after 2 and 3 days respectively. Thermotolerance of plant cells under 43°Cfirst grew rapidly but then dropped sharply. The rise of thermotolerance under all studied temperatures accompanied by the changing in the level of high and low weighting HSPs: TaHSP70, TaHSP90, TaHSP16,9 and TaHSP19. The level of expression depended on intensity of influencing temperature, exposure, as well as on a certain group of proteins hsp belongs to. For example, the accumulation of TaHSP70, TaHSP90 and TaHSP16,9 were detected in the initial period of impact 33, 37 and 43°C temperatures, while the accumulation of TaHSP16,9, TaHSP19 were detected during prolonged heat treatment. On the basis of our data, we suggest, that rise of thermotolerance of leves cells of wheat in the initial stage of impact of hardening and damaging temperatures associated with enhancing of HSP gene expression. However, the action of these gene depends on intensity, exposure of influencing temperature, as well as on a certain group of proteins hsp belongs to.