See main article: article and 2017 UEFA European Under-21 Championship.
The following is a list of squads for all twelve national teams that competed at the 2017 UEFA European Under-21 Championship. Each national team had to submit a final squad of 23 players, three of whom had to be goalkeepers.
Players in boldface have been capped at full international level either prior to the completion of the tournament or afterwards.
Age, caps, goals and club as of 16 June 2017.
Head coach: Aidy Boothroyd
Poland named their final squad on 2 June 2017.[1]
Head coach: Marcin Dorna
Head coach: Pavel Hapal[2]
Sweden named their final squad on 30 May 2017.[3] On 6 June 2017, defender Pa Konate was ruled out of the tournament after a thigh injury, and was replaced by defender Egzon Binaku.[4]
Head coach: Håkan Ericson
Head coach: Blagoja Milevski
Head coach: Nenad Lalatović
Head coach: Albert Celades
Head coach: Vítězslav Lavička
Head coach: Niels Frederiksen
Head coach: Stefan Kuntz
Jonathan Tah withdrew from the squad due to injury and was replaced by Waldemar Anton.
Italy named their final squad on 6 June 2017.[6]
Head coach: Luigi Di Biagio
| England | 36 | 13.04% | 13 | |
 Italy | 33 | 11.96% | 10 | |
 Germany | 31 | 11.23% | 9 | |
 Czech Rep. | 19 | 6.88% | 2 | |
 Spain | 19 | 6.88% | 3 | |
 Poland | 18 | 6.52% | 4 | |
 Portugal | 18 | 6.52% | 4 | |
 Sweden | 18 | 6.52% | 1 | |
 Denmark | 16 | 5.80% | 1 | |
| Macedonia | 13 | 4.71% | 0 | |
 Slovakia | 13 | 4.71% | 4 | |
 Serbia | 11 | 3.99% | 1 | |
| Others (14 leagues) | 30 | 10.87% | ||
| Total | 276 |