Captain Steven Anderson is leaving St Johnstone after 16 years, while Liam Craig, Callum Booth and Chris Kane have extended their deals until January.
Anderson is among seven players - including first-team squad members Danny Swanson, Ross Callachan and David McMillan - released by the Perth side.
The 34-year-old scored in the Scottish Cup final victory in 2014.
"It's very rare nowadays for players to be at one club for so long," said chairman Steve Brown.
"I think that says a lot about Ando as a person and a player that he's shown that loyalty. He is the St Johnstone record appearance holder and has been part of three trophy-winning sides
"Nobody will ever forget his header at the back post in the Scottish Cup final as we went on to lift the trophy in 2014.."
Out-of-contract youngsters Max Johnstone, Euan O'Reilly and Shaun Struthers are also leaving.
Midfielder Craig - second on the club's all-time appearance list - left-back Booth and youth academy graduate Kane have extended their stay until the new year.
The club remain in talks with "a number of other players" about new deals and have secured youngsters Jordan Northcott, Cammy Ballantyne, John Robertson and Oliver Hamilton on contract extensions.
St Johnstone are also searching for Tommy Wright's successor as manager, the 56-year-old having stepped down on 2 May after seven years in charge.