Since temperature distribution on the surface of the earth have not been measured at any mineralized zone, the authors have studied the method of measuring the temperatures, especially on the suitable conditions. As the result of these experiments, it has become clear that an injection needle type thermometer, in which thermister is used as thermosensitive element, is suitable to be used in a bore hole, and also that a method to prevent the soil from droping into the bore hole is necessary to minimize errors. By several tests, it is confirmed that temperature distribution could be measured at an accuracy of about 0.5-1.0°C, and by field tests at Kunitomi Mine, Hokkaido, it is proved that the outcrop exists in a relatively higher temperature zone.