Margarethe Poch-Kalous studied art history at the University of Vienna and obtained her doctorate in 1940 under Hans Sedlmayr. After working from autumn 1940 in Robert Eigenberger's Institut für Konservierung und Technologie (Institute of Conservation and Technology) at the Akademie der bildenden Künste in Wien (Academy of Fine Arts in Vienna), she obtained a lectureship in art history the following year at the Akademie Meisterschule für Kunsterziehung (Art Education Master School). She also built up the Institute library, managed the Akademie's slide archive, collaborated in Joseph Gregor's ultimately unpublished history of the Akademie and edited the catalogue to mark the Akademie's 250th anniversary in 1942. She was also involved in storing the Akademie Paintings Gallery during the Second World War. After Eigenberger's suspension as director of the Paintings Gallery in June 1945, she took over the directorship temporarily because, unlike Eigenberger, she was politically unimpeachable. She does not appear to have been a member of the NSDAP or its associated bodies. As temporary director she was responsible for the return transport of the objects stored in Lower Austria and the Salzkammergut, the rebuilding of the Paintings Gallery, which had been hit in an air raid on 12 March 1945, and the repair and restoration of many artworks that had been damaged, in some cases seriously, during the war. In spite of this work, she was not chosen to succeed as head the Akademie Paintings Gallery and was replaced in 1947 by Ludwig Münz. She continued to work in the Paintings Gallery and was employed from autumn 1947 as an assistant at the Akademie. After Münz's unexpected death, she was finally put in charge of the Paintings Gallery in 1957 and was appointed director in 1968, a position she held until her death in 1974.