Denise McAdam, 55, from Penicuik, Midlothian, said she "kept her mouth shut" when it came to the details of the private lives of Princesses Diana and Anne, as well as the Duchess of York.
She said she could write "a brilliant book" based on private information from the Duke of Cambridge and Prince Harry, but the role of royal hairdresser required discretion.
Ms McAdam is to be one of the judges in a new BBC reality show Hair, billed as a Great British Bake Off-style contest for hairdressers, which starts next week.
In an interview in the Radio Times, she said: "I've heard some very good stories from my clients over the years. I could write a brilliant book. But you have to be discreet. That's why the Queen awarded me the Royal Victorian Medal - it was for 35 years of keeping my mouth shut."