The racers battled wind gusts up to 30 mph.
Dixon's win perked up his 2009 season, which had gotten off to a disappointing start. The driver from New Zealand crashed his car at the season-opener in St. Petersburg, Fla., and finished 15th at last week's Toyota Grand Prix in Long Beach, Calif.
Dixon led the most laps Sunday and crossed the finish line 0.7104 seconds ahead of Helio Castroneves.
Tony Kanaan was third.
Dixon finished third last year after leading most of the race.
"Coming into Kansas, a lot of people told me that this place kind of owes me one," Dixon told the Kansas City Kansan. "It's nice and in the time when we needed it most Kansas gave us a payback."