Vietnam Airlines will enter the hotly contested Da Nang-Busan route with a twice-weekly service from 20 July 2019.
The airline says it will operate Airbus A321s on the route, which adds to the carrier's services to the South Korean city from Ho Chi Minh City and Hanoi.
The service will be operated just after midnight on Tuesdays and Saturdays.
Cirium Schedules data shows that Vietnam Airlines will the seventh competitor – and first Vietnamese airline - on the route. Air Busan, Asiana Airlines, Jeju Air, Jin Air, Korean Air, and T'Way air all operate on the route, with each airline operating an average of 30 narrowbody services per month.