Ghiselin Danckerts (c. 1510 – late September 1567) was a Dutch composer, singer, and music theorist of the Renaissance. He was principally active in Rome, in the service of the Papal Chapel, and was one of the judges at the famous debate between Nicola Vicentino and Vicente Lusitano in 1551.
He was born in Tholen, in Zeeland, but nothing is known of his early life. Like many of his contemporaries from the Low Countries, he may have received his early training in his homeland, going to Italy as a young adult. In his manuscript treatise Sopra una differentia musicale sententiata he asserts that he was employed by Pierluigi Carafa, member of an family in Naples. He was admitted as a singer at the Papal Chapel 21 March 1538, a position he retained, seemingly without break, until 1565. In August 1565 he was forced to retire from the papal chapel as part of a reorganization and reduction in size which followed from the reforms of the Council of Trent. The entry in the chapel records for his dismissal includes the notice: "he is without voice, he is given to women, is excessively rich, and is useless because of illness." He was granted a monthly pension of six ducats and remains in the lists among the "second class" singers from October 1565 - November 1567.
A few works of Danckerts have survived, but no complete publications. One motet which survives in manuscript is an eight-voice setting of Laetamini in domino; two other motets, for six and five voices, Suscipe verbum and Tu es vas electionis, were destroyed in the Allied bombing of Treviso on April 7, 1944, during World War II. Other surviving works include several madrigals and puzzle canons, two of which are included in Pietro Cerone's El Melopeo y maestro (Naples, 1613). An autograph manuscript source containing sacred music, like as a Salve Regina, a Magnificat, a Mass, some hymns and motets, probably composed by Danckerts, has recently come to light.