Seleucus (fl. c. 221) was a Roman usurper.
Seleucus was, according to the 5th-century historian Polemius Silvius, a usurper against Emperor Elagabalus. His identity is not known: he could be Julius Antonius Seleucus, governor in Moesia, or Marcus Flavius Vitellius Seleucus, consul for 221.