George Bruce Cortelyou (July 26, 1862 – October 23, 1940) was an American cabinet secretary of the early twentieth century.

Born in New York City, Cortelyou worked for the United States Post Office Department and came to the attention of Postmaster General Wilson S. Bissell.

After the assassination of William McKinley, Roosevelt asked Cortelyou to lead an effort to reorganize the White House.

He was educated in the public schools of Brooklyn, at Nazareth Hall Military Academy in Pennsylvania, and at Hempstead Institute on Long Island.

In 1895, President Grover Cleveland hired Cortelyou as his chief clerk on the recommendation of Postmaster General Wilson S. Bissell.

McKinley was greeting visitors at the Temple of Music at the Pan-American Exposition in Buffalo, New York, on September 6, 1901, when he was shot twice at close range by lone assassin Leon Czolgosz, a twenty-eight-year-old anarchist.

After succeeding McKinley as president, Theodore Roosevelt charged Cortelyou with transforming the White House into a more professional organization.

Cortelyou developed procedures and rules that guided White House protocol and established processes for which there had been only personal prerogative.

From 1904 to 1907, Cortelyou also served as chairman of the Republican National Committee, working for the successful re-election of Theodore Roosevelt.

To prevent future crises, Cortelyou advocated a more flexible currency and recommended the creation of a central banking system.

In 1908, the Aldrich–Vreeland Act was passed, providing for a special currency to be issued in times of panic and creating a commission that led to the creation of the Federal Reserve in 1913.