Abstract: The Çan Geothermal Field is located on a central part of the Biga Peninsula in northwest Turkey.Volcanics are the dominant rock type in this region. Alteration zones and clay minerals are verycommon in these rocks. Sedimentary rocks, low-grade metamorphics and alluvium are othergeological units observed around Çan. These units include common fracture zones because of thetectonic activity in the region. Thermal waters have reached the surface via these fracture zones.Alluvium is the most productive aquifer in all geological units. Wells drilled in this unit yieldbetween 5-30 L/s. The transmissibility and permeability coefficients of this unit are of 50-421 m2/dayand of 1.01-16.8 m/day, respectively. In this aquifer, groundwater depth changes between 0.1 and8.3m. According to the IAH (1979) water classification, these thermal waters are of the Na-Ca-SO4type, the cold waters are of the Ca-Mg-HCO3 type and the snow samples are of a mixed water type.Geothermal waters have a meteoric origin. The mean temperature, electrical conductivity and pH ofthe thermal waters have values of 44.4C, 2941 S/cm and 6.9, respectively.Geothermometer equations were used for prediction of reservoir fluid temperatures of thegeothermal system and temperature values were obtained between 46 and 203C. δD, δT and δ18Oisotope analysis showes that thermal waters in the Çan region have a meteoric origin and are aminimum of 45-50 years old.