The Britain's Got Talent runner-up previously said that she wanted the Mamma Mia! actress to portray her in her biopic.
"I'm really honoured, because I'm massively touched by her and she's got a gorgeous voice," Walters told the The Daily Telegraph.
She added that her role in the movie is far from confirmed. "Nobody has actually asked me to do it, just yet," she said.
"There's only one person I'd love to play me - and that's Julie Walters," Boyle previously told The Mirror.
"She would do the job and you just know she would do my story justice."
Watch Susan Boyle perform 'Mull of Kintyre' below: