Robert Weil (1881 – 1960) was an Austrian writer for stage and screen.
Under the pseudonym "Gustav Holm", he co-authored (with Ernst Décsey) a play Sissys Brautfahrt ("Sissy's bridal journey") which was later used for the libretto of the well-known operetta Sissi by Ernst and Hubert Marischka.
He also used the pseudonym "Homunkulus".