The actor, who plays Kurt, explained that he has already pitched the idea to the show's creator Ryan Murphy.
"I, personally, am heavily campaigning to get Julie Andrews to play my grandmother," Colfer told The TV Addict.
"Wouldn't that be great? Ryan loves the idea, and apparently somebody actually asked her at some benefit would she be interested in doing this and she said absolutely. So I guess all the cards have to play together."
Colfer also revealed that he is looking forward to Kurt having a romance during the next season.
"I know he's getting a boyfriend but I'm not sure what's happening with that storyline," he said. "Recently, Ryan has said - but things could change at any minute, because Ryan likes to change things a lot - but he's going to be a normal, everyday guy that is kind of struggling with his sexuality. Kurt kind of helps him out with it and they end up falling for each other."