The deal has caused concern in the West because Turkey is a member of NATO but the Russian missile system cannot be integrated into NATO's military architecture, Reuters said.
In addition, relations between Moscow and the Western military alliance are strained, in part because of Russia's annexation of Ukraine's Crimea peninsula.
Turkish Defence Minister Nurettin Canikli said Ankara would purchase two S-400 systems and four batteries and that all agreements were made, the state broadcaster TRT Haber reported.
Read alsoTurkey's Erdogan calls for border treaty review in Greece visit – BBCTurkey will pay 45 percent of the cost up front with Russia providing loans to cover the remaining 55 percent, Chemezov said. Moscow expected to begin the first deliveries in March 2020, he said.
Chemezov told Kommersant that Turkey was the first NATO member state to acquire the advanced S-400 missile system.
He said the Russian and Turkish finance ministries had already completed talks on financing the deal and that the final documents just needed to be approved.