The event marked the official presentation of all sports teams at the regional sports meet.
The organisers welcomed delegations to the Games and exchanged gifts with all teams' representatives.
Vietnam sent 32 athletes, coaches and officials, led by deputy chief of the delegation Hoang Quoc Vinh, to attend the event at the National Morodok Techo Sports Complex.
“We are proud to represent Vietnam at the SEA Games, where we feel warmly welcomed by the host country," said Vinh.
"We saw the organisers' attentive reception since we were at the airport. They also worked well to promote the Games. Morodok Stadium is majestic. I believe this will be a very successful festival."
Also on May 3, the main part of the Vietnam delegation left for Phnom Penh.
A total of 168 members departed from Hanoi, Ho Chi Minh City and Da Nang to join the current team in Cambodia. The rest will leave in the next few days, depending on their competition schedules.
"Vietnamese athletes will compete with the national pride and highest determination at the 32nd SEA Games," said head of the Vietnamese sports delegation Dang Ha Viet.
"We will not only be fighters representing Vietnam but also the country's ambassadors to show off our friendship, love of peace and national beauty to international friends."
The Games will officially begin on May 5 and finish on May 17 in the capital city and four other localities.
More than 12,400 athletes, coaches, officials, staff and volunteers will participate in the biennial event.
Team Vietnam has 1,003 members, including 702 athletes competing in 31 sports. They target to win between 90-120 gold medals for a place in the top three finish.
Competitors of six teams began their competitions before the opening ceremony, including ouk chaktrang chess, where Vietnam have already clinched gold in the women's doubles thanks to Pham Thanh Phuong Thao and Ton Nu Hong An. However, they will only receive their medal on May 6, when the event finishes.
On May 4, jiu-jitsu and bokator martial artists began competing. The first medals of the Games and Vietnam might be from these sports.
"The great success of the ouk chaktrang might be a lucky start for Vietnam at this Games," said Viet. "I congratulate the team and masters Phuong Thao and Hong An. Hope that other athletes will compete as well as them. "
He informed that Vietnam's Deputy Prime Minister Tran Luu Quang would visit and encourage the SEA Games team on May 4.
