Heidi Gjermundsen Broch (born 1 March 1975 in Norway) is a Norwegian actress, singer and musical artist.
Gjermundsen went to Paul McCartney's famous Liverpool Institute of Performing Arts (LIPA) in 1995-1997.
In Norway, she went to the Norwegian school Teaterhøgskolen in 1997-2000.
She is most known for playing Donna, in the original Norway production of Mamma Mia! and for playing the original Diana in the Norwegian production of Next to Normal.