Jan De Maeyer was born in 1949 in Bornem. He studied oboe, chamber music and composition (with Willem Kersters) at the Royal Conservatory in Antwerp. At the same time he studied classical philology and ancient history at the Katholieke University Leuven. In 1973 he earned higher diplomas in oboe and chamber music and a first prize in music history. This was followed by first prizes in alto oboe, harmony, counterpoint and composition. De Maeyer received the Pro Civitate Prize, the Alpaerts Prize for solfège and chamber music, the Annie Rutzky Prize, Tenuto, the Ferstenberg Prize for counterpoint and fugue and first prize at the international competition for chamber music in Colmar. As a composer he was awarded the Peter Benoit Prize for his brass quintet La Consolazione, the first prize of the Province of Antwerp (1982), the A. De Vleeschouwer Prize (1983) for Portret van 7 Romeinse Goden (Portrait of 7 Roman Gods) and the Koopal Grant for his Concerto da Camera for chamber orchestra and Het Glorierijke Licht (The Glorious Light) for symphony orchestra.

De Maeyer was manager of the Mechelen Municipal Conservatory until 2012.