She was born in Saint-Mihiel in northeastern France; her father was a bandmaster and her mother a piano teacher.
[1] She entered the Conservatoire de Paris at the age of nine, where she studied with Marguerite Long, Georges Caussade, Alfred Cortot and Charles-Marie Widor.
With Geneviève Durony, Leleu gave the premiere performance of Ravel's Ma mère l'oye in 1910.
[2] Ravel had composed his Prelude for a Paris Conservatoire sight-reading competition in 1913 and Leleu won the prize.
[1] In 1924 she took a position at the French Academy in Rome in the Villa Medici, staying there for three years before returning to Paris.