The demands on machining accuracy have been increasing lately and therefore research of thermal behaviour of machine tool structures is crucial for successful manufacturing. Generated heat diffuses into the structure of the machine tool components, this process is affected by heat sinks such as heat transfer on the surfaces and cooling systems. Meanwhile the heat warms up the structure of the machine tool and thermal dilatation deforms the structure, which subsequently affects machining accuracy in a negative way. Different systems are used to eliminate the thermal error, but their efficiency corresponds to the quality of the thermal machine tool model. The key problems of machine tool thermal error reduction are not in the thermal model itself, but in the fast, or even real-time, identification of the heat sources and the heat transfer coefficients (HTC) on the surfaces. This paper brings up a new identification method of the HTC, which is based on an analytical description