First team regulars Aki Riihilahti and Wayne Andrews will be leaving Palace in the summer after neither were offered new contracts.
The pair, whose deals both expire at the end of June, will be allowed to move on for free.
Aki has become one of the most popular members of the Palace squad since joining in 2001. He has since made 178 sppearances, scoring 14 goals along the way.
His tough tackling presence in midfield was always an asset, but he has now decided to ply his trade on the continent.
Wayne Andrews was never able to fully establish himself in the Palace first team as he was always down the pecking order behind the likes of Andrew Johnson, Clinton Morrison and Dougie Freedman. He is expected to move to QPR or return to former club Colchester.
Glenn Wilson, a 20-year-old defender, has also been released.
However, 23-year-old Mikele Leigertwood has been offered a new contract by the club.
Tony Popovic remains the only senior player out of contract this summer, and his situation will be cleared up once he returns from World Cup duties with Australia.
Four Academy players have been offered professional contracts. The quartet are Lewis Grabban, Lewwis Spence, Phil Starkey and Arron Fray.