The former world number one, seeded fourth, withstood a late rally from the world number 261 in the second set to advance to a clash with Yen-Hsun Lu of Taipei.
Oudsema smashed 17 aces but Safin, chasing his first title in more than two years, was in control from the moment he broke the American in the third game of the match.
That proved to be enough to give him the first set and he looked on course to serve out after a double fault from Oudsema gave him another break in the seventh game of the second.
But Safin, the world number 24, then lost his concentration and his serve in the 10th game as Oudsema levelled and held to lead 6-5.
It proved to be only a temporary blip, however, as Safin regrouped to win the tiebreak 7-3 and clinch victory in one hour, 28 minutes.
Safin's last tournament win came at the 2005 Australian Open, his second grand slam title.
