The driver died at the scene of the accident at Holme-on-Spalding-Moor after his Ford Fiesta collided with a yellow tractor and left the road.
His family have been informed and are being supported by officers.
Drivers are being advised to avoid the area as the road remains closed for accident investigation work and repairs.
It is likely to reopen later this afternoon.
A spokesman for Humberside Police said: "If you saw the incident or saw the Ford Fiesta travelling north on the A614 or the yellow tractor travelling south on the A614 prior to the collision we would like to hear from you."
Call 101 quoting log 57 21/01/2019.