The singer will make guest appearances in I Dreamed a Dream, which embarks on an 11-week tour of the UK later this month.
Talking about the show's popularity, she told BBC Breakfast: "The story had an appeal, a magical story, a fairy story. It was a dream come true.
"It can sort of be an example for other people, to inspire them to go on and see for themselves and to do something similar."
Elaine C Smith plays the role of Boyle in the musical, and revealed that she felt nervous when the singer joined the production herself.
"I didn't think initially that I would feel pressure, but when Susan came in I felt really nervous. I wouldn't want it to be something Susan hated."
Boyle added: "It has everything. It has drama, razzmatazz. It will make you laugh, it will make you cry.
"People will be excited and intrigued, a lot of it will be based on curiosity. I hope they like what they see."
I Dreamed a Dream is produced by Michael Harrison, and will premiere in Newcastle on Friday, March 23. Productions will then launch tours in the US and Australia the following year.
Madonna recently refused the use of her song 'You'll See' in the musical.
Listen to Susan Boyle's cover of 'Wild Horses' below: