Ann Hallenberg (born 17 March 1967) is a Swedish mezzo-soprano. She has an operatic career on the stage and concert platform around Europe. She regularly appears in major opera houses and festivals: embracing roles by Rossini, Mozart, Gluck, Handel, Vivaldi, Monteverdi, and Purcell.

Hallenberg studied at the Royal College of Music, Stockholm, with Kerstin Meyer and Erik Saedén; she undertook further study in London with Joy Mammen. Early roles included Fulgenzia in Il fortunato inganno by Donizetti at the Vadstena Academy in 1995 and Aristaeus in Rossi's Orfeo in Drottningholm in 1997, returning in 2001 as Cornelia in Giulio Cesare.

The mezzo-soprano was made artist in residence at Drottningholm for 2019 and 2020, and decided on the repertoire; in the first year it was Ariodante conducted by Ian Page. In 2021 she was appointed as Hovsångerska by the King of Sweden.