Which US president was in office during the 1929 stock market crash?

The US president in office during the 1929 stock market crash was Herbert Hoover.

Hoover became the 31st president of the United States on March 4, 1929, succeeding Calvin Coolidge. The stock market’s dramatic collapse began in October of that year, with major panic-selling on Black Tuesday, October 29. Hoover therefore occupied the White House when the crash occurred and as the ensuing economic crisis deepened.

The crash did not single-handedly cause the Great Depression, but it severely damaged confidence and exposed weaknesses in the financial system. Bank failures, falling industrial production, deflation, and mass unemployment followed. Hoover initially emphasized voluntary cooperation and balanced budgets, later supporting measures such as public-works spending and the Reconstruction Finance Corporation.

A common mix-up is choosing Franklin D. Roosevelt, whose presidency began in 1933, after the Depression was already underway. Calvin Coolidge was president during much of the 1920s, but he left office before the 1929 crash.