Beverley Callard, who played the popular character on and off between 1989 and 2011, has agreed to reprise the role and will be back on screen in October.
Liz's return storyline will see son Steve (Simon Gregson) approach her for help when he faces a crisis with girlfriend Michelle Connor (Kym Lomas). How Michelle will react to Liz's reappearance remains to be seen.
Callard told itv.com: "I am coming home and I can't wait. I am so excited to be back, I have missed Liz so it will be great to play her again. Hopefully her skirts will have got a little bit longer, but we will see!
"I have been getting texts from Simon saying we are going to rock the place and can't wait to work with Kym again and see if we can control the giggles."
Coronation Street producer Stuart Blackburn added: "I'm truly thrilled to welcome Bev back to the street, she's a fantastic actor and Liz McDonald is a truly wonderful character. It won't come as any surprise to learn that her return is sure to ruffle more than a few feathers - welcome home Liz!"
Liz was last seen on screen in April 2011, when she left Weatherfield after her on-off partner Jim (Charles Lawson) had put her through more heartbreak.
The reunited couple had hoped to buy the Rovers Return together, but Liz was left devastated when Jim was sent back to prison for armed robbery following a desperate bid to come up with the cash.
Since leaving Coronation Street, Callard has been concentrating on stage work, touring with the play Little Voice. However, she never ruled out a return to the cobbles.
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