Henri Pousseur (born 23rd June, 1929, in Malmedy, Belgium - died 6th March, 2009, in Brussels) was a composer who studied at Liège & Bruxelles music conservatories. He worked along Boulez & Stockhausen on dodecaphonic and serial music in Cologne (1954) and Milano (1957) before founding his own studio in Bruxelles (1958).

Since 1957, he taught composition in Darmstadt, Cologne, Bâle, Buffalo, then Liège before directing the city music conservatory. He was renowned for his non-stop collaboration with French poet Michel Butor: Votre Faust (1960-1968), Répons (1960-1965), Le procès du jeune chien (1974-1978), La rose des voix (1982), Déclarations d'orages (1989), Les leçons d'enfer (1991), Le Sablier du Phénix (1993).