In order to study directions of utilization of ash and slag waste from Omsk thermal power plants, the authors analyzed existing technologies for the use of these wastes in the construction materials industry, road construction, zeolite synthesis, agriculture. Despite a fairly wide range of possibilities for industrial use of ash and slag waste, the actual utilization rates of ash placed in the ash dumps of Omsk thermal power plants are close to zero. The dry ash taken from the electrofilters finds its application in the production of building materials in the Omsk region. The analysis of the possibility of extracting valuable components from ash and slag by hydrochemical methods using aqueous solutions of acids and alkalis indicatesthe implementation of these methods mainly in laboratory practice. Taking into account the content of silicon dioxide in the ash of Omsk thermal power plants exceeding 50 %, the possibility of silicon reduction from silicon dioxide by carbon was analyzed. At the same time, it is emphasized that the transition to high-temperature methods of reducing can be considered as a new stage in the utilization of potentially valuable components contained in ash and slag waste.