A diver is understood to be currently carrying out an underwater search.
The King Harry Ferry Company issued the following statement:
"We can confirm that at 16.00 on Wednesday, March 20, acar on the Roseland side on the river Fal entered the water from the slipway.
"The King Harry Ferry was at the Feock side of theriver at the time.
"The service has been temporarily suspended and emergencyservices are in attendance."
Reports from the scene suggest that one person was in the car when it went into the river.
The car is thought to have been completely submerged for approximately 30 minutes.
Emergency services are rushing to the scene after a car went into a deep flowing river in Cornwall.
The car went into the Carrick Roads at the site of the King Harry Ferry.
The car is understood to have gone straight into the river from the road on the Roseland side.
Ambulance personnel, fire crews, the coastguard and the police are all understood to be at the scene.