Goals from Burak Yilmaz and Mevlut Erdinc kept Turkey's hopes of appearing at next summer's World Cup alive.
Fatih Terim's team started this match three points behind their second-placed opponents in Group D, but this win maintains their qualification hopes with two matches remaining.
The hosts started brightly in Bucharest and inside three minutes they had seen Gabriel Torje shoot over with a 25-yard free-kick, before Ciprian Marica's header brought a save out of Turkey goalkeeper Volkan Demirel.
However, Turkey gained in confidence and after Yilmaz had seen a shot saved by Ciprian Tatarusanu, they took the lead in the 22nd minute when the same player headed in Caner Erkin's cross.
Romania threatened in the 33rd minute when Torje's shot forced defender Gokhan Gonul into a block - but the visitors finished the half on the front foot and Selcuk Inan should have done better than fire wildly over six minutes later.
Turkey had the first chance of the second half but Tatarusanu parried Umut Bulut's well-struck shot from 12 yards.
Chances were at a premium for Romania, but on the hour Alexandru Maxim saw a right-foot effort blocked by Omer Toprak. And midway through the half came the hosts' best chance, when Adrian Popa's 18-yard effort beat the goalkeeper but rebounded off a post.
Razvan Rat shot over from 12 yards with 15 minutes remaining but Turkey continued to threaten with Olcay Sahan shooting over and Bulut bringing another save out of Tatarusanu.
Maxim had a chance to earn Romania a point with two minutes remaining but his header from 12 yards failed to find the target, then in injury time Dorin Goian saw his effort from similar range caught by the goalkeeper.
And Turkey caught their hosts with a second goal in the fourth minute of injury time when substitute Mevlut Erdinc provided a cool left-foot finish.