Sophie Nélisse was born in Windsor, Ontario, but moved to Montréal with her family when she was just age four.

She began her career at the age of seven in commercials, then made her movie debut at age 10 in the 2012 French-Canadian film Monsieur Lazhar. For her performance in the film, she won a Genie and a Jutra award for Best Supporting Actress. Sophie then went on to play a role in Luc Picard's 2012 feature Esimésac before being asked to audition for the lead role of a German girl in the English-language feature film The Book Thief. She landed the part and starred alongside Geoffrey Rush and Emily Watson. In 2019, she had the lead in the sequel thriller Denizde Dehşet 2: Kafes (2019).

When not working, Sophie enjoys gymnastic classes. Her younger sister, Isabelle Nélisse, is also an actress, who, among other credits, played a lead role in the 2013 horror movie Mama.