The Third Anglo-Mysore War (1789-1792) was a war in South India between the Kingdom of Mysore and the Kingdom of Great Britain.

Tipu Sultan, the ruler of Mysore and an ally of France, invaded the nearby state of Travancore in 1789, which was a British protectorate. The resultant war lasted three years and resulted in a resounding defeat for Mysore. France, embroiled in the French Revolution and thwarted by British Naval power, was unable to provide as much assistance as Tipu had expected. The war resulted in a sharp curtailment of Mysore's borders to the profit of the Marathas, the Nizam of Hyderabad, and the Madras Presidency - all British allies or agents.

One notable military advance championed by Tipu Sultan was the use of mass attacks with rocket brigades in the army. The effect of these weapons on the British during the Third and Fourth Mysore Wars was sufficiently impressive to inspire William Congreve to invent Congreve rockets.

This was the third of four Anglo-Mysore Wars.