The ceremony is traditionally held to boost athlete morale and confidence before the competition begins.
Vietnam will send 856 members including athletes, doctors and coaches to compete in 43 out of 56 events at the Games to be held in the Philippines from November 30 to December 11.
The Vietnamese delegations aims to bag 65-70 gold medals to rank in the top three at the region’s biggest sporting event.
At the SEA Games two years ago, Vietnam ranked third in the medal tally, bringing home 58 golds, 50 silvers and 60 bronzes.
The hosts Malaysia took the lead with 145 golds, 92 silvers and 86 bronzes. While Thailand finished second with 72 golds, 86 silvers and 88 bronzes.