Walter Ladengast (July 4, 1899 – July 3, 1980) was an Austrian actor born in Vienna, Austria-Hungary. He worked extensively in film and theatre and appeared in more than 70 productions during a career spanning several decades. He is particularly remembered for his collaborations with director Werner Herzog, including The Enigma of Kaspar Hauser (1974) and Nosferatu the Vampyre (1979), in which he played Dr. Abraham Van Helsing.