O. W. Fischer (April 1, 1915 - January 29, 2004) was an Austrian actor. A leading man of German cinema, he began his career with Max Reinhardt's stage company.
He was born in Klosterneuburg near Vienna. While he enjoyed a great career, unlike countrymen Oskar Werner, Curd J├╝rgens, Maria Schell and Romy Schneider, he never made it internationally. Worse, his American break ended before it began: he was signed to star with June Allyson in a remake of My Man Godfrey in 1956, but was replaced by David Niven when Fischer reportedly lost his memory during filming. Fischer directed and starred in a 1955 movie detailing the life of Erik Jan Hanussen, the Devil's Prophet. While the film is considered highly romanticized, it assisted historians and biographers in uncovering previously unknown facts.
In the early 1970s, he retired to concentrate on linguistics and philosophy, on which he lectured and published a number of books. He died in Lugano, Switzerland of kidney failure.