The Turkish benchmark stock index closed on Wednesday at 14,331.21 points, down 1.43% from the previous close.
After starting the day at 14,552.46, the BIST 100 index decreased 208.40 points from its close on Tuesday.
The lowest for the index was 14,323.52, while the daily high 14,557.12.
A total of 74 indexes lost in value during the day, while 24 closed in the green.
The daily transaction volume reached 139.4 billion Turkish liras ($3 billion), while the overall value of the index was 13.98 trillion liras ($301.29 billion).
The USD/TRY exchange rate was 46.4970 as of 6.10 pm local time (1510GMT), the euro/lira exchange rate stood at 52.7970, and the British pound traded at 61.1925.
Gold was at $3,998.25 per ounce, while Brent crude oil futures were $73.40.