Manager Chris Coleman says he does not know when Ledley will be available to play in France.
Adam Matthews, Paul Dummett, Emyr Huws and Wes Burns were cut from Chris Coleman's training camp group.
Coleman dismissed concerns over the fitness of Gareth Bale after suffering cramp in the Champions League final.
Three players - forwards Tom Bradshaw and Tom Lawrence and defender Adam Henley  - were not considered because of injuries.
Wales begin their campaign against Slovakia on 11 June, before facing England five days later.
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Ledley, 29, missed the FA Cup final after being injured playing for Crystal Palace on 7 May.
Manager Chris Coleman, who recently signed a new deal after leading Wales to a first major tournament in 58 years, says Ledley 'is looking good' and should be back to play his part in the group stages.
"We can't say he is going to be ready, we don't know that," he said.
"He's included because of what he brings to the squad.
"He deserves the chance. The conversation is, what stage of the group games will he be available for?
"He is in the squad because he is looking good.
"In the last three or four years he has been fantastic for us."
Coleman also said striker Hal Robson-Kanu is suffering with a 'leg issue' while Joe Allen is also struggling for fitness ahead of Wales' final warm-up game in Sweden on 5 June.
Wales Euro 2016 squad:
Goalkeepers: Wayne Hennessey (Crystal Palace), Danny Ward (Liverpool), Owain Fon Williams (Inverness).
Defenders: Ben Davies (Tottenham Hotspur), Neil Taylor (Swansea City), Chris Gunter (Reading), Ashley Williams (Captain, Swansea), James Chester (West Brom), Ashley Richards (Fulham), James Collins (West Ham).
Midfielders: Aaron Ramsey (Arsenal), Joe Ledley (Crystal Palace), David Vaughan (Nottingham Forest), Joe Allen (Liverpool), Jonathan Williams (Crystal Palace), George Williams (Fulham), Andy King (Leicester), Dave Edwards (Wolves).
Forwards: Gareth Bale (Real Madrid), Hal Robson-Kanu (Reading), Sam Vokes (Burnley), Simon Church (MK Dons),  David Cotterill (Birmingham City)
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Joe Ledley has been selected in Wales' squad for Euro 2016 after returning to training less than a month after breaking his leg.