Gustav Neidlinger was a German bass-baritone, known as a performer of Wagner's villains, especially Alberich and Klingsor, from the early 1950s to the early 1970s. Born in Mainz, Neidlinger studied at the Frankfurt conservatory, where he was trained by Otto Rottsieper. He debuted in 1931 at the Stadttheater in Mainz, where he sang until 1934. In 1934 and 1935, he performed at the Stadttheater in Plauen, Sachsen. From 1935 to 1950, he was a member of the Hamburg opera, where In 1937 he took part in the world premiere of the opera Schwarzer Peter by Norbert Schultze. In 1950, he joined the Stuttgart Staatsoper, where he became very popular and was, in 1977, named an honorary member. In Stuttgart, he sang in Igor Stravinsky's The Rake's Progress. In 1956 he moved to the Vienna Staatsoper, where he had sung as early as 1941. He also sang at the Paris Opéra and at Covent Garden in London in tandem with the Stuttgart ensemble. He was honored with the title German Kammersänger in 1952.
Neidlinger's portrayal of the villainous Alberich in Der Ring des Nibelungen was recorded in Georg Solti's Decca studio recording, and Karl Böhm's 1967 performance taped live at the Bayreuth Festival.