Theodor August Konrad Loos (18 May 1883 – 27 June 1954) was a German actor. He acted on stage from 1912 to 1945. From 1913 he performed in more than 170 feature films, initially silent films.
During the Third Reich Loos was a member of the Advisory Council (Präsidialrat) of the president of the Reichsfilmkammer. After the end of the war, he returned to the theater.