Ferdinande Louise Marie Ghislaine (Fernande) de Cartier de Marchienne (Suarlée, 23 February 1872-Bruxelles 19 June 1903) was the Belgian mother of Marguerite Yourcenar.
She was a daughter of Arthur de Cartier de Marchienne
(1831–1890) and Mathilde Troye (1834–1873).
Fernande married Michel Cleenewerck de Crayencour (1853–1929) on 18 November 1900, who was the son of Michel-Charles Cleenewerck de Crayencour and Noémie Dufresne.
She died ten days after the birth of Marguerite of puerperal fever and peritonitis.