Masson was born in the commune of Houdain-lez-Bavay in the Nord department, Hauts-de-France, France, on 9 January 1914. She was the youngest of seven children, born to a clog-maker father and a tavern owner mother. At the age of 14, she was hired as a polisher in a local marble factory, where she worked for 26 years.

In 1937, she met her future husband, Louis, at the ducasse in Hon-Hergies. He worked as a machinery fitter. The couple got married on 16 April 1938. In August of the same year, the two of them had a son, Claude. Her husband left them in 1940 to serve in World War II. However, he hid in Beauvais until the war’s end after refusing to work under the Service du travail obligatoire, which forcibly enlisted French men to work for Nazi Germany.

After the war, her husband resumed his profession as a fitter. The family settled in Hon-Hergies, the village where they met, until Louis retired. They then moved into a beguinage in Bavay. In 2003, a few months after celebrating their 60th wedding anniversary, Louis passed away at the age of 89. Claude, their son, lost his wife two months later.

Until she reached 103 years old, she frequently invited her family and friends to share coffee. She cooked and cared for herself, maintaining an independent lifestyle. However, due to her increasing frequency of falls, she made the decision to move closer to her son.

Masson celebrated her 110th birthday by drinking champagne and jokingly asking about her 150th birthday. When asked about her longevity, she said that there are no secrets aside from accepting life as it is and maintaining a positive outlook towards it.

Masson currently lives in a nursing home in Marly, Hauts-de-France, France.