Born in Newlands, Cape Town in 1909, Gregoire was the son of the late D.C Boonzaier, also an artist and he therefore had early contact with other artists like Pieter Wenning, Moses Kottler, Nita Spillhause and Anton Van Wouw who often visited the family as well as a host of artistic personalities.
He was a painter of landscapes, portraits, still life, seascapes and figures and Worked in oil, watercolour, ink, wash, pencil and charcoal. He also produced un-editioned lino cuts.
Gregoire studied between 1916 – 39 at the Heatherley School of Art and the London Central School of Art, London. Moses Kottler gave him a box of paints and this set him on the way of becoming one of South Africa’s most renowned artists. His father opposed any formal training and believed that he should learn only from the various practicing artists around him. In 1932 he set up his own studio in Cape Town and in 1934 financed a trip to England from a very successful exhibition. In 1937 he returned to South Africa where he became the founding member of the New Group. He was the Chairman for a decade and for six years he represented the Cape Town SASA on the Board of the South African National Gallery, Cape Town. He painted a limited edition print of six water colours and ink drawings of District Six, Cape Town. He also visited Venice and this inspired some of his works. On 22 April 2005 Gregoire Boonzaier passed away at the age of 95 years.