Two teenage boys have been arrested for allegedly stealing a vehicle in Queens — a carjacking that left the owner seriously injured when he attempted to stop the thieves by grabbing onto the roof, police said.

The 15-year-old suspects were charged with grand larceny auto, criminal possession of stolen property and unauthorized use of a vehicle in connection to the Monday night incident in South Richmond Hill, authorities said. 

The victim, 28, was standing outside his Lexus, which he had left running, at Lefferts Boulevard and Liberty Avenue around 10:45 p.m. when three suspects jumped into his ride, police said. 

He grabbed onto the roof rack — as the suspects sped down the street in the vehicle, authorities said. 

The thief behind the wheel soon ended up striking a fire hydrant, flinging the victim off the car and causing the vehicle to flip over, cops said. 

The car owner remained in critical but stable condition at Jamaica Hospital Medical Center early Wednesday. 

One suspect was still outstanding Wednesday morning, cops said.