Katharina Müllner studied conducting, music education, and psychology/philosophy in her hometown of Vienna. After her studies she was engaged at the Landestheater Linz, where she conducted "Entführung aus dem Serail" and "Il matrimonio segreto", as well as operettas and concerts for young audiences. She was also a guest conductor at the Chemnitz Theaters with "Die Zauberflöte" and at the Aachen Theater with "Roméo et Juliette".
She has been freelancing since the 2020/21 season. Since then she successfully made her debut at the Theater St. Gallen ("Die Zauberflöte"), and at the Vienna Volksoper (Suppès "Der Teufel auf Erden"), where she also stood in for Britten's "Death in Venice". Other conducting engagements have taken her to the Deutsche Oper am Rhein, the Vienna Chamber Opera, the Robert Schumann Philharmonic, and the Wuppertal Symphony Orchestra. At the German National Theater in Weimar, she took over the premiere of "Carmen" at short notice.
In the 2022/23 season, Katharina Müllner will return to the Deutsche Oper am Rhein, the Theater St. Gallen, and the Wuppertal Symphony Orchestra, among others, and will be seen on the podium of the Philharmonic Orchestra Coburg, the Brandenburg Symphony Orchestra, and at the Theater Essen with "Carmen".