Campanus can refer to:
- Giovanni Antonio Campani called Campanus (1427–1477), Italian humanist.
- Campanus of Novara (1220-1296), Italian astrologer, astronomer, and mathematician; also:
- Campanus (crater), a lunar crater named for him
- the astrological house system named after him; see House (astrology)#Campanus
- Johannes Vodnianus Campanus (1572-1622), Czech humanist, composer, pedagogue, poet, and dramatist
- Johann Campanus (fl. 1530) Belgian Anabaptist religious reformer
- Campania, a region of Italy