The incident happened around 10 p.m. in a lot on the west side of the mall.
The 20-year-old victim told authorities she was in her car with the driver door open when a black male dressed in all dark clothing and wearing a hooded sweatshirt approached, displayed a black handgun and demanded property.
The suspect reached into the vehicle and removed the car keys.
The victim complied and handed the man her pocketbook.
He was accompanied by another man, but no description was given.
Both subjects fled on foot westbound towards East Gate Road.
There were no injuries reported.
Anyone with information is asked to call Nassau County Crime Stoppers at 1-800-244-TIPS. All callers will remain anonymous.