Hideki's racing career started with karts at the age of 12. He competed in various formula series before moving to the states to compete in the Indy Pro Series in 2007. Mutoh finished second in that series and earned rookie of the year honors.
Also in 2007, Mutoh made his IndyCar Series debut at Chicagoland Speedway with Super Aguri Panther Racing.
In 2008, Mutoh will race full-time for Andretti Green Racing, replacing Dario Franchitti, to drive the No. 27 car.
For 2009, Mutoh joined his Andretti Green Racing team for the Open Tests at Homestead in February driving the No. 27 car. He tested for a total of 224 laps and recorded a best speed of 209.995 mph. He will race the No. 27 beginning with the season opener on April 5 at the Streets of St. Petersburg in Florida.