Gallus may refer to:
- People
- several ancient Romans; see Gallus (cognomen)
- Gaius Cornelius Gallus (ca. 70 BC–26 BC), Roman poet, orator and politician (in later life, Prefect of Egypt)
- Constantius Gallus (ca. 325/326 – 354) member of the Constantinian dynasty and Caesar of the Roman Empire (351–354).
- Saint Gall (Saint Gallus), 7th century
- Gallus Anonymus, a chronicler working in 11th and 12th century Poland
- Thomas Gallus, ca. 1200-1246
- Nicolaus Gallus (1516–1570), a Lutheran Reformer
- Jacobus Gallus (1550–1591), composer
- Gallus Mag, real name unknown, an early 19th Century female bouncer at a New York bar.
- Sandor (Alexander) Gallus, Australian archaeologist
- Gallus, the Latin word for an inhabitant of Gaul
- Gallus, the singular form of Galli, the eunuch priests of Cybele
- Animal-related
- gallus, the Latin word for rooster or cockerel
- Gallus (biology), the bird genus in the pheasant family that includes the wild form of the domesticated chicken Gallus gallus.
- Gallus (constellation), The Cockerel, an obsolete constellation
- Other
- Gallus (Frankfurt am Main), former Gallusviertel, a district of Frankfurt, Germany
- Gallus (album) is the second album by the Scottish rock band Gun.
- Gallus, usually used in the plural, another word for suspenders
- Gallus, a British dialect word, chiefly Scottish, derogatory in origin and meaning "wild, a rascal; deserving to be hanged (from the Gallows)"; later meaning:
- Self-confident, daring, cheeky;
- Stylish, impressive.
- Gallus Cycles is a hand-crafted bicycle company in Fort Worth, Texas.