The pedestrian, from Tyne and Wear, was struck by a Vauxhall Corsa on Crossing Boulevard in Dartford at 18:07 GMT.
The vehicle was located in Bexleyheath and a 22-year-old man and a 20-year-old woman from Dartford were arrested.
They are being held on suspicion of causing death by dangerous driving, failing to stop at the scene of a crash and perverting the course of justice.
The victim died at the scene. His next of kin have been informed.
Officers from the Serious Collision Investigation Unit have appealed for witnesses.
PC Jamie Woodhams said: "I would like anyone who saw the vehicle and has not yet spoken to police to come forward.
"The vehicle suffered windscreen and headlight damage and was driven away from the scene towards the M25."
A man in his 20s has died after being hit by a car while crossing a road in Kent on Christmas Eve.