The 71-year-old comic actor, who voices the characters Mr. Burns, Ned Flanders and Principle Skinner, is walking away from the animated TV show after 26 seasons.
Shearer has suggested his departure has been caused by a contract dispute with bosses.
Revealing that the lawyer for The Simpsons producer James L. Brooks had delivered the news he was off the series, Shearer posted on Twitter: ”From James L. Brooks’ lawyer: ”show will go on, Harry will not be part of it, wish him the best.” He then added, “This because I wanted what we’ve always had: the freedom to do other work. Of course, I wish him the very best.”
Following his tweets, the comedian was inundated with messages of support. He tweeted: ”Thanks, Simpsons fans, for your support.”
Fox recently renewed the show for two more series taking it through to 2017 with the rest of the voice cast – which includes Dan Castellaneta, Julie Kavner, Nancy Cartwright, Yeardley Smith and Hank Azaria – signing on for the new episodes, but Shearer did not.
TMZ had reported that Shearer refused to put pen to a new contract due to unresolved merchandising issues.
Production on Season 27 has already begun without Shearer – who has starred in numerous movies including spoof documentary This Is Spinal Tap and The Truman Show – and it is not yet known who will replace him as the voice of his characters.