Hansen, who won his second career title, totaled 17-under 271. Phillip Archer (68) and Alastair Forsyth (70) shared second place at the no-cut event, which drew 27 title winners to the field.
The 33-year-old Dane chipped in from the rough on the 13th hole green for his first eagle, which gave him a four-stroke lead. Two holes later, his picked up another two strokes.
Thomas Bjorn (72) finished fourth. Bjorn began the day tied with Hansen, but a double-bogey on the sixth hole dropped him back. He had six birdies and four bogeys.
Hansen has six top-20 finishes in eight events after improving his putting.
'Soren is a huge talent,' Bjorn said. 'He has sorted his putting out this summer, which was always the weak part of his game. I've always pushed him harder and harder to make him realize how big a talent he is.'