The 32-year-old woman has had her license revoked for six months.
The dash cam of a car driving on the expressway caught her driving on the wrong side for more than two kilometers on June 10.
Despite heading in the wrong direction, the driver continuously flashed her headlights and drove at high speed.
She told the police that she did not know the road well.
The expressway runs 49 km between Cam Ranh and Dien Khanh District's Dien Tho Commune, which lies just under 25 km from the beach city of Nha Trang.
The expressway opened to traffic on May 19, allowing cars to run at a maximum speed of 80 kph and a minimum of 60 kph.
In May, a man was fined VND17 million and had his license revoked for driving on the wrong side of the Dau Giay – Phan Thiet Expressway.