It happened just after midnight on the 3800 block of North Delaware Avenue in Philadelphia's Port Richmond section.
Police say the dirt bike was traveling southbound on North Delaware Avenue at a high rate of speed when it crossed into the northbound lanes, hitting a Chevy Cobalt head-on.
The impact ejected the man from the dirt bike, where he struck a Honda CR-V that was parked on the shoulder of the road with a flat tire.
The dirt bike operator was rushed to Temple Hospital in critical condition with a fractured leg, numerous cuts and abrasions, and a serious head injury.
The man's identity has not been released.
The drivers of both the car and the SUV stayed on the scene.
The crash remains under investigation.