Milos island is located in the Aegean Volcanic Arc and is characterized by abundant geothermal resources of high temperature. Early geothermal exploration undertaken by the Institute of Geological and Mining Research of Greece includes temperature measurements in shallow wells drilled for this purpose and Schlumberger resistivity measurements of subsurface rocks. The results indicate that the eastern part of the island and especially the plain of Zefyria is the region with the highest temperature gradients and lowest apparent resistivities, hence the parts of the island most promising for high enthalpy geothermal potential