Emma Stone said she gets frustrated when directors keep offering her similar roles.
The Superbad and Easy A star says she regularly receives scripts in which she would play "the sarcastic interest of the guy".
"It's kind of mind-boggling to think that people decide to only see the one thing. 'Oh you did that, let's do that again, and again, and again'," Emma said.
And the 22-year-old said her latest role in The Help, as a spirited young writer fighting for racial equality in 1960s Mississippi, was a welcome challenge.
"It was pretty incredible - I think we all felt very excited at the prospect of being part of a project like this," she added.
Meanwhile, her co-star Viola Davis - who plays black maid Aibileen in the movie - said she had also experienced typecasting in her career.
"I get the asexual, strong, wise kind of person who doesn't need God, Buddha, Jesus, nothing. Because I know the answers," she quipped.
"I see myself as different from all that. I see myself as a little ditsy, a little quirky. And then when I walk into a room it doesn't matter how many lashes I put on or how cute I look, they're like, 'Asexual strong matriarch'. So after a while you're like 'Damn, what am I projecting?'"
:: The Help in in cinemas now.