The Battle of Surabaya was fought between pro-independence Indonesia soldiers and militia against British and British Indian troops as a part of the Indonesia National Revolution.

The peak of the battle was in November 1945. The battle was the heaviest single battle of the revolution and became a national symbol of Indonesian resistance. Fighting broke out on 30 October after the British commander, Brigadier A. W. S Mallaby was killed in a skirmish. Although the Colonial forces largely captured the city in three days, the poorly armed Republicans fought for three weeks, and thousands died as the population fled to the countryside.

The battle and defense mounted by the Indonesians galvanized the nation in support of independence and a gang of collaborators without popular support. It also had the effect of convincing Britain that wisdom lay on the side of neutrality in the revolution; within a few years, in fact, Britain would support the Republican cause in the United Nations.

Considered a heroic effort by Indonesians, the battle helped galvanize Indonesians and International support for Indonesian Independence. 10 November is celebrated annually as Heroes' Day.