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 for 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.
Heidi has two kids with her husband, the Norwegian actor Nicolai Cleve Broch.