Turkey's benchmark stock index BIST 100 fell down 61.64 points or 0.06 percent to open at 108,293.18 points on Thursday.
The banking sector index dropped 0.31 percent while the holding sector index rose 0.11 percent.
Among all sector indices, the insurance sector index was the best performer gaining 1.06 percent, whereas the banking sector index saw the biggest decline.
The U.S. dollar/Turkish lira exchange rate slightly rose to 3.7590 at 9.30 a.m. local time (0630GMT) Thursday, compared with 3.7300 at Wednesday's close.
Brent crude oil price went down to $58.34 per barrel on Thursday at 9.30 a.m. local time (0630GMT) compared with $58.37 at 06.00 p.m. local time (0300GMT) the previous day.
At Wednesday's close, BIST 100 was up 1.07 percent hitting 108,354.83 points with a trade volume of 5 billion Turkish liras ($.1.3 billion).