This article shows the 12-player roster of all participating teams at the 2023 FIVB Volleyball Men's U21 World Championship.
[2][3] Head coach: Gholamreza Momeni Moghaddam A 12-player squad was announced on 4 July 2023.
[18][19] Head coach: Mateusz Grabda A 12-player squad was announced on 4 July 2023.
[22] Head coach: Michel Mariën A 12-player squad was announced on 5 July 2023.
[23][24] Head coach: Jan Svoboda A 12-player squad was announced on 30 June 2023.