Geronimo Stilton is a beloved character and the titular author created as part of a children's book series originally by Elisabetta Dami. The series features adventures and mysteries solved by Geronimo Stilton, a mouse who lives in Mouse City. He is the editor of the fictional newspaper The Rodent's Gazette. Geronimo Stilton books are primarily aimed at children aged six to twelve and are renowned for their engaging narratives and unique typography that visually represents the story's elements.

Since its inception, the series has expanded to include several spin-offs such as the Thea Stilton series, focusing on Geronimo's sister, and the Cavemice and Spacemice series. The books are characterized by their humor, simple language, and educational content, often incorporating factual information about geography, history, and culture.

The persona of Geronimo Stilton is presented as a shy, nervous, and mild-mannered mouse who enjoys telling stories about his unpredictable adventures with his friends and relatives. The character's universal appeal is also reflected in the multimedia adaptations that include television series and a wide range of merchandise.