Long-term data from meteorological stations have been used in assessing the thermal state of the soil layer in large depressions of the Prebaikalia and Northern Transbaikalia. We examine the characteristics of temperature distribution in depth over a yearly cycle for seasonally freezing and permafrost soils. For the Baikalian type depressions we carried out a spatial differentiation of the lowest and highest (having regard to the temperature lag with depth) monthly mean soil temperatures. It is concluded that within a single depression the thermal regime of the soil fluctuates over a very broad range. On the other hand, an identical situation with the temperature regime can occur in different depressions.Keywords: Baikalian type depressions, soil temperature, seasonal freezing, permafrost.