The present invention relates to medicine and veterinary medicine, and specifically to measurements for diagnostic purposes by measuring the temperature of parts of the body and can be used in medical practice for diagnosing illnesses and for monitoring dynamics of an illness during treatment. The technical result achieved when using the claimed method consists in increasing accuracy and clarity and in simplifying the technical implementation. The method comprises inputting an image of the region of the body of a biological subject under investigation into a computer database, with said image being output to a monitor of the computer, wherein the measurement points for measuring the temperature in the region of the subject under investigation are displayed in the image of the subject on the monitor screen and, once the measurements have been taken and the results of the measurements have been processed in the computer, an image of the temperature field is generated by a computer program using the image of the region of the subject under investigation.