"Hannah Montana" was not inspired by "Lizzie McGuire" in "any shape or form," TMZ has learned ... following Hilary Duff's comments that she was "sure" the 'Lizzie McGuire Movie' helped shape the show.

We caught up with the creator of "Hannah Montana," Michael Poryes, who says Disney pitched him the ​idea to create a show about a popstar ... and he came up with the concept in a small garage office in Los Angeles.

He tells us there was "zero" inspiration derived from "Lizzie McGuire" -- he had never even seen the movie -- saying he'd watched maybe 1 or 2 episodes of the series when he went to brainstorm ideas that would eventually lead him to "Hannah Montana."

He's not hating on Lizzie at all ... he said it's a "clever" show, and achieving such success opened the door for him to create "That's So Raven," Disney's first 4-camera sitcom.

Overall, Michael tells TMZ he's proud of 'Hannah' and his creative process.

As you may have seen, Hilary Duff watched some of "The Lizzie McGuire Movie" for a chat with Vanity Fair, and noted the similarities in the secret popstar plotlines between the film and "Hannah Montana." She noted ... "I think that Disney knew they were tapping into something when this, like, worked so well ... So I'm sure it was some source of inspiration."

Looks like she may have spoken too soon ... but regardless, we're glad both Hilary and Miley Cyrus got "The Best of Both Worlds" in their respective franchises!