The prince asked whether the movie version of Harry Potter and the Sorcerer's Stone, currently being filmed in Britain, would live up to the book.
"He said he can't wait, and he wanted to know whether it was true to how I saw the story in my mind," Rowling said after the investiture ceremony at Buckingham Palace. "I said that it was."
"It's always very difficult for TV and film adaptations to live up to a book," said 35-year-old Rowling, who received her award for services to children's literature.
"But I had a lot of input in this one and although it can never be 100 percent, I think it's going to be great."
Rowling's four Harry Potter books, recounting the adventures of Harry and his friends at Hogwarts School of Witchcraft and Wizardry, have sold more than 30 million copies around the world.