After a long and bitter dispute that divided the sport, the IndyCar and Champ Car series were united in February and the year's first race will be the GAINSCO Auto Insurance Indy 300 at the Homestead-Miami Speedway.
Dixon earned the first spot on the starting grid for Saturday's race by turning four laps around the 1.5-mile oval in 213.341 miles per hour.
A rules change for this year will force the competitors to qualify with four consecutive laps.
Starting alongside Dixon will be Ed Carpenter. It will be the best starting position in Carpenter's career.
Dario Franchitti and Sam Hornish have both left open-wheel racing this year to take part in the NASCAR series. But Helio Castroneves will still be racing on the circuit, as will Tony Kannaan and Dan Wheldon.