Richard Russell Riordan Jr., best known as Rick Riordan, is an American author famous for his work on the Percy Jackson & the Olympians series. His books have been translated into forty-two languages and have sold more than thirty million copies in the United States alone.

Riordan's first significant breakthrough came with The Lightning Thief in 2005, the first novel in the five-volume Percy Jackson and the Olympians series, which features adolescents placed in a Greco-Roman mythological setting.

Before his success with children's fiction, Riordan wrote the Tres Navarre series, a mystery series for adults, winning the Edgar, the Anthony, and the Shamus awards.

Riordan also contributed to The 39 Clues series by writing its first book, The Maze of Bones, and has penned other notable series such as The Heroes of Olympus, The Kane Chronicles, and Magnus Chase and the Gods of Asgard. In 2021, he published Daughter of the Deep and later co-authored The Sun and the Star with Mark Oshiro in 2023.

Rick Riordan lives in Boston with his family and is actively involved in overseeing TV/film adaptations of his works.