She was a student at the Paris Conservatoire, where she was given a premier prix in 1891.
She founded the Marguerite Long-Jacques Thibaud International Competition in 1943 with violinist Jacques Thibaud. Its name was changed to the Long-Thibaud-Crespin Competition in 2011 to provide for the inclusion of singers along with the traditional pianists and violinists.
Her husband, Joseph de Marliave, was killed in action while fighting in World War I.
Her close friend, Maurice Ravel, dedicated his Piano Concerto in G major to her. She performed its premiere.