Firmus (disambiguation)

Firmus (died 273) was a usurper during the reign of Aurelian.

Firmus may also refer to:


 * Firmus (4th-century usurper) (died 375)
 * Firmus and Rusticus, 3rd century saints
 * Firmus Energy, a Northern Ireland energy company
 * Admiral Firmus Piett, a fictional character in Star Wars