2005 AFF U-23 Youth Championship winners Thailand were the defending champions, as there was no competition from 2006 to 2018 and the 2011 edition was cancelled.

The following teams from member associations of the AFF entered the tournament (excluding Australia).

[4] A final squad of 23 players (three of whom must be goalkeepers) must be registered one day before the first match of the tournament.

In the knockout stage, penalty shoot-outs were used to decide the winner if necessary.

All 16 matches were broadcast live and free to access in Cambodia, some ASEAN countries and internationally via the Football Federation of Cambodia (FFC)'s official Facebook page, although in the Khmer language.