Their meals include green papaya with dried shrimp salad and beef gazpacho with oil dressing.
The Vietnamese squad are staying at a 4-star hotel in Phnom Penh along with 15 other teams.
The 32nd SEA Games will take place from May 5-17 in Cambodia – though several sports kick off a week early, with most events being held in the capital Phnom Penh.
The football competition will begin on Saturday, April 29.
A chef prepares hu tieu noodle, a popular dish in southern Vietnam.
Cambodia is the first SEA Games host to provide meals, transport and accomodation to all participants for free. The country earlier planned to charge each person $50.