After the war, he studied at the Universität der Künste Berlin and at the Humboldt-Universität zu Berlin, where he received his doctorate in 1924 with the dissertation Die Methodik im Schulgesang der evangelischen Lateinschulen des 17.
[2] In 1939, Preußner went to the Mozarteum in Salzburg, where he became lecturer and managing director and headed the city's concert office.
[2] In 1959, Preußner became full professor, president of the Academy for Music and Performing Arts, director of the International Summer Academy Mozarteum Salzburg [de], secretary general of the European Association of Conservatoires and editor of the music pedagogical bibliography.
In addition to several guest professorships in the United States, Preußner became a member of the board of directors of the 1960 Salzburg Festival.
[2] Preußner was the godfather of the cellist Wolfgang Boettcher, who later married his niece Regine Vollmar.