The aim of this paper is to investigate water resources in Turkey. Annual rainfall varies from 220 torn to 2500 mm with an average of 643 mm, which means total volume of 501 km(3) and average annual potential of surface water is 186 km(3) and 95 km(3) of this amount potential can be feasibly developed. Ground water reservoirs are estimated to be around 12 km(3). As a result of construction of 700 dams, with different types, purposes and sizes, 140 km(3) of water is being stored in the reservoirs. Total hydropower potential of Turkey is annually 433,000 GWh. Almost 50% of the total potential is technically exploitable, and 29% is (122,322 GWh/year) economically exploitable.