A man from Kirton was arrested on suspicion of causing death by dangerous driving following a crash on the A1 at South Witham on Saturday teatime.
The 30-year-old man suffered minor injuries in the crash and was treated at Peterborough City Hospital.
He has been released on police bail.
Police have not yet named the 24-year-old man from Glenrothes, Fife, who died in Peterborough City Hospital.
The accident happened at 4.55pm and the southbound lane of the A1 was closed until about 11.40pm.
Police have appealed for witnesses to contact their collision investigation hotline on 01522 558855.