Ahmadinejad will hold talks with President Abdullah Gul and Prime Minister Tayyip Erdogan.
Turkey has reportedly offered to help mediate the dispute between Iran and the West over Tehran's nuclear program, but Hassan Gashgavi denied that Turkey was acting as an intermediary on the issue.
He said however that Tehran and Ankara had a good bilateral relationship and that Iran regarded Turkey as "one of the most important countries in the region."
Iran said last Friday that recent talks in Geneva with the UN nuclear watchdog had been constructive.
At talks with Iran in Geneva on July 19, the six nations - China, Russia, the U.S., France, Britain and Germany - put forward a package of trade and nuclear technology incentives, demanding a response from Tehran within two weeks.
The answer took two and a half weeks to arrive, and European Union foreign policy chief Javier Solana said the letter did not contain a clear response to the proposals.
Iran has repeatedly dismissed Western accusations that it is seeking to build nuclear weapons under the guise of a civilian nuclear program. The Islamic Republic has also consistently insisted on its right to peaceful nuclear research.
