The Organization for Security and Co-operation in Europe (OSCE) said on Sunday that no discrepancies were reported during the elections so far.
The delegation started its on-site observation in Lieutenant Kalmaz Primary School in capital Ankara.
Speaking to reporters, Ambassador Audrey Glover, head of the election observer delegation, said they will continue following the polls closely till they end.
"There are no obstacles to the OSCE delegation, and we continue to observe the election in the methodology we employ all the time,” she said.
The delegation will hold a press briefing at the Sheraton Hotel in Ankara at 3.00 p.m. local time (1200GMT) on Monday.
Some 415 observers from eight international organizations have been deployed to watch Turkey’s presidential and parliamentary elections.
The Organization for Security and Cooperation in Europe (OSCE) has sent 234 observers, while the Parliamentary Assembly of the Organization for Security and Cooperation in Europe (OSCEPA) sent 72, the Parliamentary Assembly of the Council of Europe (PACE) deployed 35, and the Parliamentary Assembly of the Mediterranean (PAM) sent 10 observers.