Group A has hosts Cambodia, Timor Leste, Philippines and Brunei; while group B has Indonesia, Malaysia, Myanmar and Laos, according to the draw results on Wednesday.
The tournament will be held Feb.14-26 in the Morodok Techo and Prince stadiums in Cambodia.
Vietnam had been grouped with Thailand in the previous edition of the tournament as well. They had taken the top group spot but lost 0-1 to Indonesia in the semifinals before beating Cambodia 1-0 in the third-place playoff. Thailand entered the finals, but lost 1-2 to Indonesia.
Coach Dinh The Nam will manage the team for the U23 AFF Cup. The tournament is seen as part of preparations for SEA Games 31 that Vietnam hosts in May.
SEA Games 31 will be the last tournament with Park Hang-seo as coach of the U23 team. After that, he will only coach the national team, with the U23 team set to be managed by another South Korean coach.
Since Park took over the national and U23 teams in 2017, Vietnam beat Thailand twice, at King’s Cup and U23 AFC Championship qualifiers, and drew three times. The first defeat against Thailand under Park was at the AFF Cup this year when the defending champs lost 0-2 after two legs of the semifinals to bow out of the tournament.