The 49-year-old singer became an overnight sensation last year after she appeared on the TV competition show "Britain's Got Talent" and the clip of her performance was watched by millions on the Internet.
"I'm writing this book to try to show that you shouldn't judge a book by its cover and I hope it will benefit other people," the BBC quoted Boyle as saying.
"When I strutted on to the stage for that audition, I was a scared wee lassie, still grieving for my mother, not caring how I looked," Boyle added. "I think I've grown up a lot in the last year, become more of a lady, and I'm not so frightened any more. My story demonstrates that you shouldn't just look at the label, you should look at the whole person, emotionally, physically, mentally and spiritually, and I hope that telling it will show that dreams are not impossible, if you've got courage and a willingness to go on -- no matter what the circumstances."
Boyle's debut album "I Dreamed a Dream" topped the U.S. and U.K. album charts for several weeks.