Alistair Wilson, of New Pitsligo, near Fraserburgh, was taken to hospital with serious injuries, but died on Monday.
The 51-year-old was driving a grey Vauxhall Astra when he crashed into a silver BMW 320 on the A90 at around 09:30 BST.
Both of the men had to be cut free from their vehicles at the crash site near the Murcar roundabout.
Police have appealed for witnesses.
A man has died in hospital following a head-on collision on Saturday, Police Scotland have confirmed.