An earthquake measuring 6.0 on the Richter scale jolted western Turkey at 20:15 GMT on Thursday, the U.S. Geological Survey said.
The epicenter, with a depth of 4.60 km, was initially determined to be at 39.11 degrees north latitude and 29.12 degrees east longitude.
The quake occurred at 23:15 local time in western province of Kutahya, the semi-official Anatolia news agency quoted Turkey's Kandilli Observatory as saying.
Turkey's Kandilli Observatory said that the epicenter of the quake was Simav town, adding that people living in surrounding provinces and towns also felt the quake.
There were no immediate reports of casualties or damage.