The 15-year old was seriously injured when the car in which she was a passenger collided with a parked white Mercedes in Goring yesterday (Tuesday).
Emergency services were called to Alinora Avenue at 5.10pm.
The silver Peugeot 206 contained five people all local to Worthing, two men aged 20 and 21, a 14-year old girl, a 15-year-old girl and a woman aged 18.
Two of the occupants, the 15-year old and the 14-year old girl were freed from the car by firefighters.
The 15-year old was taken to St Georges Hospital in London by air ambulance where she is currently in a critical condition.
The 14-year old girl and the 18-year old woman were taken by road ambulance to the Royal Sussex County Hospital in Brighton where their conditions are described as stable.
The two men in the car were arrested on suspicion of driving with excess alcohol and of causing serious injury by dangerous driving.
They are currently in custody for interview and further enquiries.
Sergeant Alan Spicer of the Sussex Road Policing Unit at Arundel said; “We are keen to hear from anyone who may have seen this crash or may have seen the small silver hatchback in the area just beforehand. If you have any information please contact us via 101 or email collision.appeal@sussex,pnn.police.uk quoting Operation Oracle.”