A 34-year-old man has been arrested on suspicion of murder after the discovery between Polperro and Looe at 5.30pm on Friday (28th June).
Police were called to a layby close to West Wayland Caravan Park and upon arrival discovered the body of the 28-year-old woman in a Ford Mondeo car.
Detectives have launched an investigation into the death which is being treated as unexplained at this time.
A post mortem examination has been carried out but police await the results of further forensic tests to determine the cause of death.
The man, from Bromsgrove, Worcestershire, was arrested at the scene and taken to Newquay police station. He has been released on police bail pending further enquiries.
Anyone with information is asked to contact police by telephoning 101, quoting reference BE/13/0331.