| Competition: | Men's U21 World Championship |
| Continent: | World |
| Gender: | Men |
| Year: | 2003 |
| Size: | 150px |
| Dates: | 23–31 August |
| Teams: | 16 |
| Venues: | 2 |
| Cities: | 1 |
| Champions: | POL |
| Title Number: | 2 |
| Website: | http://www.fivb.org/EN/Volleyball/Competitions/Junior/Men/2003/ |
| Last: | 2001 FIVB Volleyball Men's U21 World Championship |
| Next: | 2005 FIVB Volleyball Men's U21 World Championship |
The 2003 FIVB Volleyball Men's U21 World Championship was the 12th edition of the FIVB Volleyball Men's U21 World Championship. It was held in Tehran, Iran from August 23 to 31, 2003.
| Means of qualification | width=18% | Vacancies! | width=32% | Qualified |
|---|---|---|---|---|
| Host country | 1 | |||
| 2002 NORCECA U21 Championship | 1 | |||
| 2002 South American U21 Championship | 2 | |||
| 2002 European U21 Championship | 1 | |||
| 2002 Asian U21 Championship | 3 | |||
| 2002 African U21 Championship | 2 | |||
| European Qualifier | 6 | |||
| Total | 16 | |||
| width=40 | Rank | width=180 | Team |
|---|---|---|---|
 Poland | |||
| Bulgaria | |||
| 4 | |||
| 5 | |||
| 6 | Iran | ||
| 7 | |||
| 8 | |||
| 9 |  Canada | ||
| 13 | |||
| 12–man Roster[2] | |
| Artur Augustyn, Marcel Gromadowski, Michał Kaczmarek, Marcin Kryś, Marcin Możdżonek, Bartłomiej Neroj, Arkadiusz Olejniczak, Michał Ruciak, Dariusz Szulik, Michał Winiarski, Mariusz Wlazły, Paweł Woicki | |
| Head coach | |
| Grzegorz Ryś |