The Kansas City massacre was the shootout and murder of four law enforcement officers and a criminal fugitive at the Union Station railroad depot in Kansas City, Missouri, on the morning of June 17, 1933. It occurred as part of the attempt by a gang led by Vernon C. "Verne" Miller to free Frank "Jelly" Nash, a federal prisoner. At the time, Nash was in the custody of several law enforcement officers who were returning him to the U.S. Penitentiary at Leavenworth, Kansas, from which he had escaped three years earlier.

Charles "Pretty Boy" Floyd was identified by the FBI as one of the gunmen. However, there is evidence to suggest that Floyd was not involved.