| Conflict: | Battle of Cádiz (1640) |
| Partof: | the Franco-Spanish War (1635–1659) |
| Date: | 21 July 1640 (Julian calendar) |
| Place: | Bay of Cádiz |
| Result: | French victory |
| Combatant1: |  Spanish Empire |
| Commander1: | Jerónimo Gómez de Sandoval |
| Commander2: | Jean Armand de Maillé-Brézé |
| Strength1: | 10 galleons, 1 patache |
| Strength2: | 24 galleons, 12 fireships |
| Casualties1: | 1 galleon burned, 1 patache sunk |
| Casualties2: | Unknown |
The Battle of Cádiz (1640) was a naval battle in the Franco-Spanish War (1635-1659), which took place on July 21, 1640, when a French squadron under Jean Armand de Maillé-Brézé attacked a Spanish convoy coming from the Americas.
The attack occurred just in front of the coast of Cádiz. Armand de Breze employed a hitherto unknown tactic to attack the Spanish convoy from both sides. The Spanish lost a galleon and a small vessel but the convoy completed its journey and delivered most of its cargoes including its silver bullion. French losses are unknown.