Development players Ryan Inniss, Jerome Binnom-Williams, Jake Gray, Reise Allassani, Connor Dymond and Luke Croll have been offered new deals with Crystal Palace.
The under-21 side topped their division in the U21 Professional Development League 2 this season and the six players have impressed sufficiently to be offered new terms with the Eagles.
These are in addition to Hiram Boateng who signed a contract extension earlier in the season.
Development boss Gary Issott said: "Ryan has had a couple of good loan spells at Yeovil Town and Port Vale, Jerome has been a part of Southend United's promotion bid and Jake had a great start to the season by travelling with the first-team to America as well as making his first-team debut in the Capital One Cup.
"Connor has captained the under-21s and Luke has steadily progressed and made the left centre-half spot his own over the course of the year.
"Hiram Boateng signed a new deal earlier in the season and has been a consistent performer and has been in and around the first-team squad, so we're delighted with all their progress."
Meanwhile Kyle de Silva, Gus Sow, Sam Magri, Morgan Ferrier, Fisayo Adarabioyo, Sonny Black and Michael Chambers will be leaving the club after they weren't offered new deals.
"It was a tough decision to release Kyle as he's been here since he was 13-years-old and played for the first-team," Issott added. "He'd got to an age where if he wasn't in the team then he had to go and find first-team football somewhere else.
"Gus has been here since he was 11 but he's had an injury-hit season, Michael came from the Ryman Premier League and has success in the Conference so he's made it to a higher level.
"The others were just on month-to-month contracts and we gave them a chance to put themselves in the shop window and find themselves a new club.
"Everyone here is hands to the pump trying to help them find new clubs and a few are training with other clubs around the country so we're confident they'll be OK for next season.
"Releasing players is so difficult and they're not easy decisions to make, but the age they are and the quality they've shown means they can have careers in full-time football."