Henri Masson began his studies at the Royal Athenaeum in Brussels. He moved to Canada in 1921 and attended the Ottawa Art Association and the Ottawa Art Club. His first solo exhibition took place in Toronto in 1938 at the Picture Loan Society.
He was a member of the Canadian Society of Painters in Watercolor, the Society of Graphic Arts and the Canadian Group of Painters in 1941. He chaired the Conference of Canadian Artists in Ottawa in 1945.
In 1994, Henri Masson was made an Officer of the Order of Canada.