Mary Lou Fallis (born April 22, 1948) is a Canadian opera singer. She performs both serious opera roles and comedic shows as the character Primadonna, a satirical take on popular stereotypes of opera divas.
Born in Toronto, Ontario, Fallis began her education as a singer with her grandmother, Jennie Bouck.
She also won an ACTRA award. In 2014, she was awarded an honorary Doctor of Music from Carleton University.