The actress’ character, Bianca Jackson, was last seen in Walford back in 2014.
Upon her return, Bianca will be reunited with her troubled daughter, Tiffany, played by Maisie Smith.
Announcing the news, Jon Sen, EastEnders’ executive producer, told The Sun: “When I joined the show in January, bringing Bianca Jackson back to the Square was high on my wish-list.
“I’m thrilled to announce that Patsy’s agreed to return to reprise her iconic creation in a blistering storyline that will grip fans this autumn.
“There is no one more excited than me to see her step back into Albert Square again. I simply cannot wait.”
Patsy joined EastEnders in 1993 and her character Bianca soon became a small screen icon, with her wedding to Ricky Butcher (played by Sid Owen) drew in an audience of more than 22 million.
Patsy then left the soap in 1999, before returning in 2008 and leaving again in 2014.
After her most recent departure, Patsy and her family relocated to Malibu, California, where she’s continued working as an actress.
Bianca will be back on screen for a short stint later this year.