Clemens Heinrich Krauss (31 March 1893 – 16 May 1954) was an Austrian conductor and opera impresario, particularly associated with the music of Richard Strauss.
Krauss was born in Vienna to Clementine Krauss, then a 15-year-old dancer in the Vienna Imperial Opera Ballet, later a leading actress and operetta singer, niece of the prominent nineteenth-century operatic soprano Gabrielle Krauss. His natural father, Chevalier Hector Baltazzi (1851-1916), came from a family of wealthy Phanariot bankers resident in Vienna. Baltazzi's older sister Helene was married to Baron Albin Vetsera and was the mother of Baroness Mary Vetsera, who was accordingly Clemens Krauss' first cousin.
Krauss sang in the Hofkapelle (Imperial Choir) as a Vienna Choir Boy. He graduated from the Vienna Conservatory in 1912, after studying composition with Hermann Graedener and theory with Richard Heuberger there. He was then appointed chorus master in the Brno Theater (1912-1913), where he made his conducting debut in 1913. The famous Romanian soprano Viorica Ursuleac, who often sang under him, became his second wife.
He became a close friend of Richard Strauss, and even wrote the libretto for his opera Capriccio which he premiered in Munich in 1942. He also conducted the premieres of Strauss's operas Friedenstag and Die Liebe der Danae. During the early 1940s, he taught at the Mozarteum University of Salzburg where among his pupils was composer Roman Toi.