A young Australian man living his dream of working for Disney in Florida has been killed by a hit-and-run driver.

Mahmoud Arabi, 22, was dressed in his Disney uniform at an Orlando intersection early on Monday morning when a car hit him.

"The victim was crossing with two other people and unfortunately they were crossing against the light," Sergeant Kim Montes of the Florida Highway Patrol told AAP.

The car had the green light but failed to stop after the accident.

Arabi, believed to be from Melbourne, was in a critical condition and taken to an Orlando hospital.

He died on Wednesday not long after his mother arrived from Australia to be by his side.

The Disney college exchange program attracts young students from around the world, allowing them to get on-the-job experience at the entertainment conglomerate's theme parks, including Disney World in Florida.

Sgt Montes said it was believed the car's side mirror struck Arabi.

The mirror was found at the crash scene and from its serial number it was identified as being from a green Ford.