The first three of six reels made in 1923 were discovered by the National Film Preservation Foundation at the New Zealand Film Archive.
Hitchcock was the writer, assistant director, editor and art director of "The White Shadow." The film was directed by Graham Cutts. Hitchcock's own directing debut came two years later.
Foundation Director Annette Melville said the reels of "The White Shadow" were found among films donated to the archive by the family of New Zealand projectionist and collector Jack Murtagh.
No other copy of "The White Shadow" is known to exist.
The silent melodrama stars Betty Compson in a dual role as twin sisters, one angelic and the other "without a soul," according to Melville.
A restored print of "The White Shadow" will be shown Sept. 22 at the Samuel Goldwyn Theater at Academy of Motion Picture Arts and Sciences headquarters in Beverly Hills. The program also will feature two recently rediscovered short films, including one directed by and starring silent-era superstar Mabel Normand.
The Associated Press contributed to this report.