Abstract: Geological, geophysical and geochemical data, as well as data from other related areas, are key elements to predict a geothermal system. Heat source, migration pathways for fluids or heat, geothermal reservoir, cap rock, and heat preservation conditions are all critical for the formation and preservation of a working geothermal system. At the same time, the topography, seismicity, wildlife protection, environmentally sensitive area and infrastructure all should be evaluated for geothermal exploration. Our survey on geothermal databases showed that the historically accumulated data have been organized in different geothermal databases under different formats. These databases belong to only a few countries and as a result accumulate data mainly from their area. Large amount of data from other regions is still scattered and in an unorganized condition. Geographic Information System tools and mathematical methods might be helpful to solve this problem. Play fairway analysis with fuzzy logic technique or machine learning approach could be used to analyse the different types of data, and then predict the hidden geothermal system.