The world's growing energy demands carry the energy into an important stage. Crude oil will be able to supply increasing demand until peak world production is reached. Forecasts show that this peak time is about 2020. Turkey and the world will deplete economically recoverable fossil resources by the end of the 21st century. The energy gap caused by declining fossil resources has to be filled by expanding production of other sources. Geothermal energy is one of the most important options for filling this gap. Turkey is located in the Alp Himalayan Tectonic Belt and has high potential geothermally. In fact, Turkey is the seventh country in the world while the first country in Europe of the abundance of geothermal resources. In this article, the history and development of geothermal, its application, and current situations in the world and the situation in Turkey with European Union perspective are examined by giving the facts and statistical information for the last 10-year period.