A collision in Colac has left a man in hospital with head and internal injuries.

The driver of a Ford ute was airlifted to a Melbourne hospital after he lost control of the vehicle going over a railway line.

The incident happened at about 12.30pm as the Ford was heading south on Flaxmill Road near the ALC meatworks building.

Two children were also in the car at the time, both were transported to Geelong hospital.

The children were able to get out of the car and were taken to a Geelong hospital while the driver needed to assisted by SES personnel.

Police are still investigating the cause of the accident, anyone with footage or information is urged to contact Colac police.