Born in Bolzano, she studied singing with Alessandra Amadii, Paola Folli and Roberta Rigotto and took part in workshops and seminars with Elizabeth Howard, Jack Poppell, Maria Pia De Vito and Franco d'Andrea. In 2013 she was the leading actress in "Das Ballhaus" at the Vereinigte Bühnen Bozen. Since 2014, Greta Marcolongo has repeatedly appeared as a singer in various productions at the Tiroler Landestheater Innsbruck, including in Enrique Gasa Valga's plays "Dante.Inferno", "West Side Story", "Chicago" and "Maria de Buenos Aires" and in Marie Stockhausen's "Der blaue Engel". In 2018 she completed her bachelor's degree in jazz music. In 2022 she was part of Gasa Valga's Evita production in Kufstein. In 2023 and 2024 she and her band were part of the ensemble of the play "The Great Gatsby" at the Tiroler Landestheater and the Deutsches Theater in Munich. In 2024, she appeared in the music and theater performance "Amore Tricolore" at the Tiroler Landestheater under the new artistic direction. As artistic director, she conceives and directs cultural projects, festivals and concerts for various organizations and associations in South Tyrol, writes and designs music programmes for RAI South Tyrol and Haydn Orchestra Bolzano-Trento.