A 30-mile queue developed after police closed a clockwise section of the motorway between junction 9 for Leatherhead and junction 10 for Wisley.
Police said the crash, which happened at about 5am on Thursday, involved an articulated lorry, a London taxi and a red Citroen.
The closed section of the motorway is not expected to reopen until at least mid-afternoon.
Some pictures posted on social media show the jacknifed lorry after it slammed into barriers at the side of the road.
A Surrey Police spokesman said: “The lorry driver has been taken to hospital by air ambulance with life threatening injuries. The occupants of the other vehicles are not injured.
“The M25 is closed between J9 for Leatherhead and J10 for Wisley, and is likely to be closed until mid-afternoon while emergency services are at the scene and a large diesel spill is cleared.
“Motorists are asked to find an alternative route at this time.
“Officers are appealing for anyone who witnessed the collision, or who may have dash cam footage of the driving of any of the vehicles before the collision, to get in touch.”
Anyone with information should contact Surrey Police by calling 101 and quoting the reference number PR/P19155923.
