The single vehicle collision was reported to police at around 7am on the B1395 Wood Lane near South Kyme.
A police spokesman said: “The male driver of the van sustained injuries, but it’s unclear at this stage if those injuries are serious or not.”
Fire crews from Sleaford and Woodhall Spa attended and used tools and manpower to help assist the driver from the vehicle.
It is blocked both ways between Skinners Lane (the Golf Club turn) and the A153 Main Street/Sleaford Road.
Traffic is said to be coping well, but the road was confirmed closed from 7.30am.
The spokesman added that the A17/B1395 westbound junction was closed shortly after 8am to allow emergency services to deal with the incident.