She wrote the Harry Potter series, but the illustrations were done by various artists, including:
* Mary GrandPré: Illustrated the first four US editions of the Harry Potter series.
* Jim Kay: Illustrated the entire series for a special illustrated edition.
* Levi Pinfold: Illustrated the "Fantastic Beasts and Where to Find Them" film tie-in book.
Rowling has stated that she doesn't have the artistic skills to illustrate her own books, and she prefers to let other artists bring her characters to life visually.