Marie-Louise Meilleur (29 August 1880 – 16 April 1998) was a Canadian supercentenarian and Canadian longevity recordholder.

On 4 August 1997, with the death of famous Jeanne Calment of France, she become the oldest validated living person.

She died at the age of 117 years, 230 days, from a blood clot in East Ferris, Ontario on 16 April 1998. Her death make Sarah Knauss the oldest validated living person in the world.

At the time of her death, she was the 2nd longest lived person ever behind only Jeanne Calment, although Shigechiyo Izumi still considered as older than Meilleur, so Meilleur considered as the 3rd place. (Lucy Hannah case was validated in c.2003 and debunked in c.2019.)

By 2022, she remains the 6th oldest person in history, behind Jeanne Calment, Kane Tanaka, Sarah Knauss, Lucile Randon and Nabi Tajima.

For Nabi Tajima case, it is said to be she probably one year younger, so Meilleur might be the 5th.