The former 'Sex and the City' star will be a "frazzled and eccentric" editor of the acclaimed fashion magazine's website when she makes her guest appearance in the musical drama and show bosses think she is "hilarious".
The show's co-creator and executive producer Ian Brennan said: "Sarah Jessica Parker is gonna be running Vogue.com.
"That's sort of where we encounter this character, who's sort of frazzled, eccentric, hilarious. It's gonna be good."
Sarah Jessica's storyline sees her encounter both Rachel Berry (Lea Michele) and Kurt Hummel (Chris Colfer) in New York, but Ian refused to be drawn on how.
Asked if it was via Kurt receiving an internship, he said only: "We'll see."
One person who is keen to see that happen is Darren Criss, who plays Kurt's boyfriend Blaine Anderson.
He told 'Access Hollywood': "I've had a good ride, sort of hanging on to Chris' coattails. If I could continue to do that, that'll be great... And if that yields work with Sarah Jessica Parker, I'll be thrilled. That'd be so cool. I love her."
Meanwhile, Ian also revealed more details of Kate Hudson's forthcoming guest role, including the character's name.
He said: "Kate Hudson will play Cassandra July. And she's gonna be able to sing and dance. It's going to be pretty awesome. She'll be Rachel's dance teacher at NYATA and it's gonna be good."