The singer told Teen Vogue that she had signed up to play a small part in the Oscar-winning film, but had to drop out due to scheduling conflicts.
Perry said: "There was a time when I was going to be involved in The Help.
"Just a small part, I wasn't going to be Emma Stone or anything, but I couldn't because the shooting schedule conflicted with the release of my record."
She continued: "I was upset about that. I knew it was going to be an important film. Not that I need to do drama first, but I do want to do something that makes a strong impression."
Perry did not confirm which specific role she was planning to play in the film.
The US release date for Perry's 3D concert movie Katy Perry: Part Of Me was recently announced as July 4.
> Katy Perry 'Part of Me' video branded "propaganda for the Marines"
> Katy Perry fans to help shape 'Part of Me' 3D concert movie on Twitter
Watch the full trailer for Katy Perry: Part Of Me below: