Former England forward Alan Smith has been released by MK Dons, along with the club's all-time record goalscorer Izale McLeod.
Winger Ryan Hall has also not been offered a deal by the League One side.
Midfielders Stephen Gleeson, Antony Kay and Mark Randall are considering contract offers at Stadium MK.
The club have exercised options in Lee Hodson and Ben Reeves' contracts which will see the pair remain at MK Dons for at least another 12 months.
Former Leeds, Manchester United and Newcastle striker Smith joined Dons in July 2012 after a successful loan spell.
The 33-year-old made 83 appearances for the club, scoring three goals.
McLeod, 29, returned to MK Dons last year for a second spell at the club and has scored 71 goals in total.
"The club would like to place on record its appreciation for the efforts of those players who are leaving and wish them every success for the future," said a statement.