Club also announces details of new deals for two defendersMillwall have confirmed that seven players will leave the club following the conclusion of the 2015/16 season.
Senior squad quartet Carlos Edwards, Ed Upson, Lee Martin and John Marquis have been informed that their contracts will not be extended beyond the end of June and are to be released from the club.
Three members of Millwall's U21 Elite Development Squad - Jack Powell, Chris Parr and Keaton Wood - will also be departing The Den having not been offered new deals.
Loanee Chris Taylor is returning to parent club Blackburn Rovers.
Mark Beevers, whose contract is due to expire next month, is in discussions with Neil Harris regarding a new deal.
Fellow defenders Byron Webster and Joe Martin have had clauses in their contracts activated meaning they will remain at The Den for a further 12 months.
Harris told millwallfc.co.uk: "First and foremost I want to thank all the players who are leaving us for their immense dedication and hard work during their time at the club.
"They handled my decision like true professionals and I wish Carlos, Ed, Lee, John, Jack, Chris and Keaton nothing but the very best of luck for their future careers.
"It is always incredibly hard to make decisions like these but they are done so with what I feel are the club's long-term best interests at heart.
"My task now is to continue shaping a squad which can once again challenge for promotion in the 2016/17 season."
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