George Grossmith (11 May 1874 – 6 June 1935), known until 1912 as George Grossmith Jr., was an English actor, theatre producer and manager, director, playwright and songwriter, remembered for his work in and with Edwardian musical comedies and 1920s musicals. He was also an important innovator in bringing cabaret and revue to the London stage. Born in London, he took his first role on the musical stage at the age of 18 in Haste to the Wedding (1892), a West End collaboration between his songwriter and actor father and W. S. Gilbert.

Grossmith soon became an audience favourite playing "dude" roles – fashionable but unserious characters. Early appearances in musicals included George Edwardes's hit A Gaiety Girl in 1893, and Go-Bang and The Shop Girl in 1894. In 1895, Grossmith left the musical stage, instead appearing in straight comedies, but after a few years he returned to performing in musicals and Victorian burlesques. Early in the new century, he had a string of successes in musicals for Edwardes, including The Toreador (1901), The School Girl (1903), The Orchid (1903), The Spring Chicken (1905), The New Aladdin (1906), The Girls of Gottenberg (1907), Our Miss Gibbs (1909), Peggy (1911), The Sunshine Girl (1912) and The Girl on the Film (1913). The lanky Grossmith was often paired with the diminutive Edmund Payne. At the same time, he developed a reputation as a co-writer of musicals and revues, often adding jokes into others' librettos.

Grossmith established himself as a major producer, together with Edward Laurillard, of such hits as To-Night's the Night (1914), Theodore & Co (1916) and Yes, Uncle! (1917). He wrote the long-running revue series that began with The Bing Boys Are Here (1916), scheduling these projects around his naval service in the First World War. He produced, co-wrote, directed and sometimes starred in, Kissing Time (1919), A Night Out (1920), Sally (1921), The Cabaret Girl (1922), The Beauty Prize (1923) and Primrose (1924). He also continued to appear in other producers' shows, including The Naughty Princess (1920) and No, No, Nanette (1925).

Later he performed in such pieces as Princess Charming (1926) and began a film career in 1930, both as an actor and, from 1932, chairman of London Film Productions Ltd.