The actress, who plays Stella Price, has said when her current contract expires in April 2014 she will not seek a renewal. Her character will leave our screens in June 2014.
Michelle said in a statement: "Stella Price has been a revelation to play. So much has happened to the character since we discovered she was Leanne's real mum. From catching Karl with barmaid Sunita to her near death experience in the Rovers fire, I've loved playing Stella and will be very sorry to leave her behind."
Corrie producer Stuart Blackburn said: "We wish Michelle every happiness as she moves on to pastures new. Her character has made a tremendous impact and has deservedly earned her the status of a classic Coronation Street matriarch."
He added: "When an actor decides to leave a programme like Corrie, it means the writing team can creatively scale new heights. We promise the tour de force that is Stella Price will leave with a bang."
According to The Sun, 51-year-old Michelle, who has also appeared in EastEnders, is thought to be leaving in order to spend more time with her family.
Her announcement comes just days after Corrie lost another high profile star, Chris Fountain. ITV sacked the Tommy Duckworth actor on Monday night (19 August) after he was unmasked as the man behind an online rapper who posted offensive videos referencing violence and rape.