Guido Deiro was born on 1 September 1886 in Salto, Cuorgnè, Piedmont, Italy. He was married to Yvonne Le Baron de Forrest, Ruby Lang, Mae West and Julia Tatro. He died on 26 July 1950 in Loma Linda, California, USA.
Secretly married Mae West in 1914. West filed for divorce from Guido Deiro on the grounds of adultery on July 14, 1920. The divorce was granted by the Supreme Court of the State of New York on November 9, 1920.