The internal structure of the castings depends on the super-cooling level of the melt upon contact with the face of the mold. In die casting technology, the relatively cold mold material comes into the contact with substantially higher temperature melt in short successive cycles. This causes high thermal fluctuations that cause cyclic thermal stress of the mold. The contribution evaluates the heat balance of the mold during casting of a particular type of the cast and describes the distribution of the temperatures in the mold volume during one casting cycle. The contribution presents a comprehensive picture of thermal processes occurring between the cast, the mold and the surroundings.