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)
Pick the XI that you think can take Wales to the final of Euro 2016 - and then share it with your friends using our team selector.

Beavon smashed home just before the half-hour mark to inflict a second successive defeat on Swindon, following their loss at Barnsley last weekend.
The striker punished hesitancy among the Swindon defence with a clinical volley, the Brewers' first ever goal at the County Ground.
Wes Thomas dragged wide from inside the penalty area for the home side.
Jon Obika and Louis Thompson also missed the target while Yaser Kasim had a free-kick pushed over by Jon McLaughlin as Burton held out for the win.
Burton Albion boss Jimmy Floyd Hasselbaink told BBC Radio Derby:
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"I'm very happy. I think when you're coming to Swindon, you know what they're about. They can keep the ball for fun and they can test your nerves and get overloads in certain areas, but we made it very uncomfortable for them. We didn't let them get into their stride, we didn't let them play their game and get into their rhythm.
"For us, it was all about winning the ball back in their half and trying to penetrate in the last third and I think we did that really well.
"We should have scored more goals and that's something we need to work at, but I must say I'm extremely happy with how the team has worked today. We were very solid and we were quite creative with the ball at times, but the belief needs to become greater because they can do a lot more than they think."
Joe Ledley has been selected in Wales' squad for Euro 2016 after returning to training less than a month after breaking his leg.
[NEXT_CONCEPT]
Stuart Beavon's first-half strike moved Burton to the top of League One with their first ever win at Swindon.