With one game to play, the win put Iceland top of the group on 19 points, two ahead of Croatia, who drew 1-1 with Finland. Ukraine also rose to 17 points after beating Kosovo, while Turkey were left on 14 points and out of contention.
Johann Gudmundsson put Iceland ahead in the 32nd minute, latching on to a cross from Jon Bodvarsson at the back post to fire the ball past Volkan Babacan in the Turkish goal.
The visitors doubled their lead seven minutes later when Bodvarsson slipped the ball between two defenders to Birkir Bjarnason who fired the ball beyond Babacan, drawing boos from the raucous crowd in the northwestern Turkish city of Eskisehir.
Turkey's hopes of fighting their way back into the game were dashed early in the second half when Kari Arnason knocked the ball in from close range in the 49th minute, after a corner was headed back across the goal mouth by Aron Gunnarsson.
The pattern was set early in the match as Turkey's efforts to break down the solid-looking Iceland defence bore little fruit and the visitors repeatedly looked to hit Turkey on the counter attack.
After the third goal, Iceland were content to sit back and absorb the pressure from Turkey for much of the second half as the hosts looked to salvage pride, but even a consolation goal eluded them.
Iceland will host Kosovo in their final game while Croatia will play away against Ukraine. Turkey will travel to Finland for their last game.
(Writing by Daren Butler; Editing by Toby Davis)
