Gallus may be:

• Quintus Roscius Gallus (c. 126 - 62 BC), Roman actor
• Gaius Asinius Gallus, Roman consul
• Gaius Cornelius Gallus (69 - 26 BC), first Roman governor of Egypt, writer of elegiac verse
• Trebonianus Gallus (251-253), Roman emperor
• Constantius Gallus (-354), cousin of Constantius II
• Saint Gall (7th century)
• Gallus Anonymus, a chronicler working in XIth and XIIth century Poland
• Jacobus Gallus (1550-1591), composer
• Thomas Gallus
• gallus, a Roman term for one of the corybantes, followers of Cybele

The bird genus Gallus in the Pheasant family includes the wild form of the domesticated chicken Gallus gallus.