Black Tuesday was the 1929 stock-market crash day when the Dow Jones Industrial Average lost nearly 12%.
Black Tuesday occurred on October 29, 1929, after heavy selling on the New York Stock Exchange. It followed Black Thursday on October 24 and Black Monday on October 28, creating a sequence of panic-driven declines.
The crash did not by itself cause every aspect of the Great Depression, but it became its most famous financial symbol. Falling share prices weakened investors, banks, and businesses, while broader problems such as debt, overproduction, and reduced spending deepened the downturn.
A common mix-up is treating Black Tuesday as the entire crash. The market continued falling after October 29 and did not reach its low until July 1932.