Was born in Bonsecours (Péruwelz) on October 23, 1893. He obtained First Prizes for organ, harmony, counterpoint and fugue at the Brussels Royal Conservatory of Music.
Later he studied privately composition and orchestration with Paul Gilson. Absil was awarded several composition prizes among which was the Second Grand Prix de Rome in 1921. One year later he became director of the Etterbeek Music Academy. In August 1930 he was appointed professor of practical harmony at the Brussels Conservatory. In 1934 he founded ""La Sirène"", an association promoting contemporary music and organising concerts in Belgium and abroad, and in 1938 the periodical ""Revue internationale de Musique"". One year later became professor of fugue at the Brussels Conservatory and Queen Elisabeth of Belgium invited him to teach counterpoint and fugue at the ""Chapelle Musicale Reine Elisabeth"" which she had just founded. Jean Absil developed a quite personal style and his tremendous creative urge resulted in a very large productivity. He composed five symphonies, numerous orchestral works, concerti, piano music, chamber music and a lot of vocal music. He succumbed to a stroke on 2 February 1974 at Uccle (Brussels).