Algorithms of the solution of inverse problem of heat transfer, the combining analytical and numerical methods of the calculations providing an opportunity of definition of thermal flow and factors of heat exchange in crystallizer in real time in established mode of continuous casting of cylindrical ingot are developed. Averages for cycle heat transfer coefficients on borders casting—crystallizer and crystallizer-water are calculated. Dependence of heat transfer coefficients on border casting—crystallizer from time of a cycle is approximately estimated.