Hermann Wiedemann (7 March 1879 – 21 June or 1 July 1944) was a German operatic baritone and academic teacher. He was a long-term member of the Imperial Court Opera in Vienna from 1916, where he appeared as Faninal in Der Rosenkavalier by Richard Strauss 196 times, and as Beckmesser in Wagner's Die Meistersinger von Nürnberg 155 times. He was Beckmesser also in a recording from the Salzburg Festival 1937, conducted by Arturo Toscanini. He performed internationally at leading opera houses and festivals, such as the Teatro Colón of Buenos Aires and the Zoppoter Festspiele. He appeared in the world premieres of Wolf-Ferrari's I gioielli della Madonna in Berlin, Busoni's Die Brautwahl in Hamburg, and Lehár's Giuditta in Vienna.