Rose, a 29-year-old Briton, collected his first PGA Tour championship, bouncing back from a four-shot deficit to finish with an 18-under 270, three ahead of third-round leader Fowler.
Fowler fell off the pace after his tee shot at the par-three 12th found a water hazard and he ended up taking a double-bogey to find himself two shots behind. Fowler ended with a 1-over 73, good for sole possession of second at 15-under 273.
Third place was shared by Bo Van Pelt (69) and Ricky Barnes (73) at 12 under 276.
Phil Mickelson shot a 69 to end in a three-way tie for fourth with Tim Petrovic (74) and Ryan More (68) at 11-under 277, missing a chance to overcome defending champ Tiger Woods at the top of the world rankings. Mickelson needed a victory to gain the top spot.
Woods played all four rounds of a tourney for the first time since the Masters in his return from a neck injury. He finished with a 72 and ended in a 19th-place tie at six-under 282.