Turkey's stock exchange dropped 0.11 percent, or 114.28 points, to open at 101,738.20 points on Monday.
On the first transaction day of the week, the banking and holding sector indices decreased 0.19 percent and 0.03 percent, respectively.
Among all sector indices, the textile leather sector index posted the highest increase, up 0.49 percent, while the food beverage sector index saw the worst drop, down 1.22 percent.
On Friday, Borsa Istanbul's BIST 100 index closed at 101,852.48 points, down 0.52 percent, with a 5.7 billion-Turkish lira ($1.33 billion) trade volume.
The U.S. dollar/Turkish lira exchange rate climbed to 4.3320 as of 9.30 a.m. local time (0630GMT) on Monday. It was 4.2950 at Friday's close.
The euro/lira exchange rate was up at 5.1840 from 5.1390 on Friday.
The price of Brent oil prices per barrel $76.66 as of 10 a.m. local time (0700GMT) Monday. It was $77.12 at the previous close.