Emergency services were called to the scene on the B1190 at Bardney at 9.48am where a silver Mercedes-Benz A220 and a silver Ford Galaxy had been involved in a collision.
The 12-year-old boy, a passenger in the Galaxy, was sadly pronounced dead at the scene.
The male driver of the Mercedes has been taken to hospital. The status of his injuries is currently unknown.
The roads have been closed following the incident while emergency services attend.
If anyone saw the collision, or has information relating to the incident, call Lincolnshire Police on 101, quoting Incident 141 of January 16, or email [email protected] .
Alternatively, call Crimestoppers, anonymously, on 0800 555 111.