Petit-Prince is an asteroid moon that orbits the larger asteroid 45 Eugenia. It was discovered in 1998 by astronomers at the Canada-France-Hawaii Telescope on Mauna Kea, Hawaii.

Petit-Prince was named in 2003 after Antoine de Saint-Exupéry's character The Little Prince, who was in turn based on the Prince Imperial, son of Empress Eugenia. It is an extremely appropriate name, since The Little Prince in the novel lives on an asteroid. In the book, the little prince's asteroid has no name, but it has a unique identifier: B612

Petit-Prince is 13 km in diameter, compared to 45 Eugenia's 214 km. It takes five days to complete an orbit around Eugenia.

Petit-Prince was the first asteroidal moon to be discovered by a ground-based telescope. Previously, the only known moon of an asteroid was Dactyl, discovered by the Galileo space probe around 243 Ida.

See also:

• 2578 Saint-Exupéry
• 46610 Bésixdouze, named B-six-twelve in French