The 2005–06 TFF Lig A (known as Iddaa Lig A for sponsoring reasons) was the second-level football league of Turkey and the 43rd season since its establishment in 1963–64. At the end of the season, in which 18 teams competed in a single group, Bursaspor and Antalyaspor, which finished the league in the first two places, and the play-off winner Sakaryaspor were promoted to the upper league, while Mersin İdman Yurdu, Yozgatspor and Çanakkale Dardanelspor, which were in the last three places, were relegated.[1][2]