Jean Joseph Nicolas Guillaume Lekeu (20 January 1870 – 21 January 1894) was a Belgian composer of classical music.
Lekeu was born in Heusy, a village near Verviers, Belgium. He originally studied piano and music theory under Alphonse Voss, the director of the brass band at the local conservatory. In 1879, his parents moved to Poitiers, France. He continued to pursue his music studies independently while at school, composing his first piece at the age of 15. From 1885 onwards, he regularly composed new music, especially for piano, and studied harmony and violin from 1887 under Octave Grisard.
In June 1888, his family moved to Paris where he began to study philosophy. He was introduced to the works of Téodor de Wyzewa and continued his studies under Gaston Vallin. In August 1889, he traveled to Bayreuth to see the operas of Richard Wagner. On his return, he studied counterpoint and fugue privately with Cesar Franck. Franck encouraged him to continue composing; after Franck's death in the autumn of 1890, Wyzewa introduced him to Vincent d'Indy, who taught him orchestration and encouraged him to compete for the Prix de Rome, awarded in Brussels. In 1891, he won second prize in the competition for the cantata Andromède.
In 1892, d'Indy introduced Lekeu to Octave Maus, then secretary of Brussels-based Le Cercle des XX.Eugène Ysaÿe commissioned a work from him, the Violin Sonata in G Major, which premiered in March 1893, and which is highly regarded.
Lekeu contracted typhoid fever from a contaminated sorbet in October 1893. He died in his parents' home in Angers on 21 January 1894, the day after his 24th birthday. On 26 January 1894, he was buried in a small cemetery in Heusy.
Lekeu's personal style was present in his earliest compositions. In 1887, he said "Bien plus, ce sera bizarre, détraqué, horrible, tout ce qu'on voudra; mais, du moins, ce sera original" ("Even more, it will be weird, mad, horrible, anything you like, but at least it will be original").