William Waller Lewis (3 November 1860 – 1 November 1915), known on stage as Lewis Waller, was an English actor and theatre manager, well known on the London stage and in the English provinces.

After early stage experience with J. L. Toole's and Helena Modjeska's companies from 1883, Waller became known, by the late 1880s, for romantic leads, both in Shakespeare and in popular costume dramas of the Victorian and Edwardian eras. He attracted a large number of female admirers, who formed themselves into a vocal and conspicuous fan club. He also tried his hand at management of tours in 1885 and 1893 and then became an actor-manager at the Theatre Royal, Haymarket in the mid-1890s. After the turn of the century, he returned to management, and remained an actor-manager for the rest of his career, both in London and on tour.

Despite his commercial success in such parts as the title roles in Booth Tarkington's Monsieur Beaucaire and Arthur Conan Doyle's Brigadier Gerard, Waller greatly preferred acting in Shakespeare, in which his roles ranged from Romeo to Othello. Among the roles he created was Sir Robert Chiltern in Oscar Wilde's 1895 comedy An Ideal Husband.