The crash happened at just after 8.00am this morning, Thursday, close to Belmot Golf Club in Belmot Road, Needwood, near Burton On Trent.
A West Midlands Ambulance Service spokesman said: “When crews arrived they found a black car some distance into a field and a red car, both which had extensive damage.
“An ambulance was first on scene and was quickly backed up by the crew of the Midlands Air Ambulance from Staffordshire in a response vehicle as they are based just three minutes away at Tattenhill.
“There were three people in the black car. A young girl had suffered serious injuries. She became unconscious while being treated. She was airlifted by the Derbyshire, Leicestershire and Rutland Air Ambulance to the regions paediatric major trauma centre at Birmingham Children’s Hospital.
“A man estimated to be about 40 who was in the back of the car was treated for serious injuries. He was anaesthetised at the scene, immobilised and had a pelvic binder put in place before being airlifted by the Midlands Air Ambulance from Cosford to the major trauma centre at Royal Stoke University Hospital.
“The driver, a 46 year old man, was taken by land ambulance to Burton Queens Hospital with a knee injury and abrasions to his head.
“There were two people in the red car. A 10 year old boy in the back suffered minor chest pain from seatbelt and was taken by ambulance to hospital in Burton.
“The boy’s father, who was driving, was uninjured but was travelling to the hospital to be with his son.”