Abstract: Many geothermal fields in Kütahya including Eynal, Çitgöl ve Naşa (Simav), Ilıcasu-Abide (Gediz),Muratdağı, Yoncalı, Emet, Yeniceköy, Dereli, Göbel, Ilıca (Harlek), Sefaköy ve Hamamköy (Hisarcık) andŞaphane are located between Kütahya and Simav active faults in Western Turkey. Studied area in Simav(Kütahya) is situated in the north of Simav Fault and indicated as an active fault zone in the active faultmaps of Turkey. This area is fairly active region in terms of earthquakes occurred in the instrumental period and has many geothermal systems. Most of these geothermal fields are located on active fault zones.Approximately 735 earthquakes (M>3.0) occurred between May 2010 to May 2013, including 1 earthquake with the magnitude of greater than 6.0 at Gediz in 1970 and 4 earthquakes with the magnitude ofgreater than 5.0 at Simav in 2009, 2011 and 2012. Data from a monitoring study during three years (2010-2013) from thermal springs in Eynal, Çitgöl ve Naşa geothermal fields which located at Simav (Kütahya)were used in this study. This study tried to find out relationship between geothermal springs and activefaults, and relationship between hydrochemical features of geothermal waters and high seismic activity.The results of this study indicated that some physic-chemical parameters of geothermal waters change especially increasing temperature, increasing Cl- ion value and decreasing SO4-2 ion value with earthquakeswith has 5.0 and greater magnitude value.