In continuous casting the quality of cast steel slabs and billets, thermal stress, surface defects and cracks formation are highly dependent on the temperature distribution along the entire continuously cast blank. The main attention is usually paid to the surface temperatures and particularly to the corner temperature distributions. However, from the technological point of view the temperature distribution in the core of cast blank, which is highly related to the metallurgical length and to the unbending process, is very important as well. Therefore, monitoring of temperature field of cast blanks, its prediction by using numerical models as well as controlling and optimization tasks of secondary cooling strategy are priority issues for technologists, quality engineers, and operators of continuous casting machine. The paper is aimed at the thermal analysis and the investigation of temperature field of cast billets by utilizing the original numerical model of temperature field of continuously cast steel billets. In particular three grades of steel with different carbon content and the 200x200 mm billets, which are cast in Železiarne Podbrezová in Slovakia, are considered. The performed study and presented software tools can be used by engineers to enhance the quality and productivity of continuously cast steel and to improve the competitiveness of steelworks. and Obsahuje seznam literatury