Formula Two driver Henry Surtees died after a motor racing accident at Brands Hatch, police said.
The son of 1964 Formula One world champion John Surtees was airlifted to hospital following the accident at the Kent race circuit yesterday but died not long after.
Surtees was struck on the head by a wheel and tyre from the car of Jack Clarke, which spun into the wall exiting Westfield Bend during the second of this weekend's races at Brands Hatch, near Swanley.
He was knocked unconscious by the impact and his car collided with the barriers at the following Sheene corner.
A spokesman for Kent Police confirmed the 18-year-old had died.
He added: "Kent Police is not involved because it was a motor racing incident as opposed to anything suspicious.
"It appears it was a tragic accident."
The race was red flagged while Surtees was removed from the car and taken to the medical centre where he was prepared for his transfer to hospital by helicopter.
A spokeswoman for South East Coast Ambulance Service said it attended the incident at 1.30pm yesterday and a man was airlifted to the Royal London hospital with head injuries.
Surtees claimed his first F2 podium finish on Saturday when he finished third in the weekend's opening race at Brands Hatch.
He secured a drive in F2 over the winter after a breakthrough year in 2008, when he contested the Formula Renault UK Championship and Winter Series, and made his debut in British Formula Three at the final round of the campaign, when he claimed a victory and a podium finish for Carlin in the National Class.
His father, John Surtees, is famously the only man to have won world titles on both two and four wheels.
He claimed multiple 500cc motorcycle world championships before winning the F1 crown with Ferrari in 1964.
The 75-year-old also fielded his own Team Surtees cars in F1, F2 and Formula 5000 in the 1970s.