Emergency services attended however the man was pronounced dead at the scene.
A full report will be sent to the Procurator Fiscal.
Sergeant Craig McNeill, of the Divisional Road Policing Unit at Inverurie, said: “Our thoughts are very much with the man’s family and friends at this time.
“Officers responding to this crash had parked a distance away due to weather conditions. On returning to their van they discovered a tree had fallen on it. No one was injured.
“Any witnesses to this crash or anyone with information is asked to contact 101 quoting reference number 2999 of 26 November.”