The incident took place at around 11.30am on May 12, when the 41-year-old woman was parked on Montgomerie Terrace.
She was first approached by an unidentified woman who reached in and assaulted her, and shortly after that a man – who was present during the assault – stole some of her things from within the car.
The woman was left upset and suffered minor injuries
DC Robertson of Saltcoats CID, said: “This incident occurred in broad daylight and left the victim with minor injuries and understandably upset.
"I would please ask that anyone who may have witnessed the incident, has CCTV or dashcam footage or knows the identity of those responsible to contact Saltcoats Police Office quoting incident 2303 of May 13.”
If you would like to report information anonymously you can call Crimestoppers on 0800 555111.