Juliette Mars, born in France, regularly performs at venues such as the Theater an der Wien, the Wiener Volksoper, as well as the Théâtre des Champs-Élysées in Paris and the Théâtre du Capitole Toulouse. In 2020/21, she returned to the Theater an der Wien, among others, where she portrayed Natalia in a new production of Leoncavallo's rarely performed opera, Zaza. In early 2021, she returned to Toulouse as Larina in Eugen Onegin, and in the spring, she played Brangäne in Tristan und Isolde at the Wiener Kammeroper, directed by Günther Groissböck. Juliette Mars was a member of the Vienna State Opera ensemble, where she could be heard in over 45 roles spanning from the Baroque to the Modern era. Some of her notable roles included Smeton in Anna Bolena, Meg Page in Falstaff, Siébel in Faust, Marquise de Berkenfield in La Fille du régiment, Suzuki in Madama Butterfly, Stéphano in Roméo et Juliette, Tisbe in La cenerentola, the Kitchen Boy in Rusalka, and Flosshilde in Das Rheingold and Götterdämmerung.
Even during her time at the Vienna State Opera, she regularly returned to her homeland, France, where she performed at the Opéra de Nice as Muse/Nicklausse in Les Contes d’Hoffmann and as the Kitchen Boy in Rusalka. At the summer festival Opéra en plein air, she took on the title role in Carmen. At the Théâtre des Champs-Élysées, she portrayed the Second Lady in Die Zauberflöte and Siébel in a concert performance – a recording of which will soon be released on CD. She was also heard in the title role of Rossini's La cenerentola at the Opéra de Marseille.
At the Wiener Volksoper, she has performed roles such as Muse/Nicklaus in a new production of Hoffmanns Erzählungen. Her debut at the Theater an der Wien in 2017 was as Margret in Wozzeck, and she also sang the roles of Titania/Puck in Oberon and the Kitchen Boy in Rusalka there. She has achieved further success as Dorabella in Così fan tutte at the Festspiele Schloss Laxenburg, and in the contemporary opera Hemma by Bruno Strobl at the Carinthischer Sommer, she sang the title role. Juliette Mars regularly performs recitals with Cécile Rester on the piano.