Grégoire Michonze (Michonznic) was born into a Jewish family in Kishinev (Bessarabia) in the Russian Empire (now the Republic of Moldova) on 22 March 1902, and studied at the local art school, where he learned to paint traditional icons in tempera, before going on to study at the Academy in Bucharest. In 1922 he travelled to Paris via Greece, Istanbul and Marseilles, a journey which strongly influenced his later landscape painting. In Paris he entered the École des Beaux-Arts, and met Max Ernst who later introduced him to the Surrealists, notably André Breton, Paul Éluard, and Louis Aragon, though he gradually moved away from their influence to pursue his own personal path as a landscape and figurative artist. In 1924 he met Soutine with whom he developed a strong friendship. Between 1934 and 1936, Michonze exhibited at the Salon des Surindépendants, creating elaborate compositions, which he later described as "Surreal naturalism". In 1937 he moved to New York and Massachusetts, marrying the Scottish artist Una Maclean on his return to France. During the Second World War, he enlisted in the French artillery in 1939, was taken prisoner in June 1940 and held until December 1942 in Stalag XC at Nieburg-on-Weser, 60 km from Bremen in Germany. His wife, Una, remained in Paris in order not to lose contact with Michonze and was subsequently imprisoned in several French camps, between January and August 1941, where she continued to receive her husband's letters from Germany. He returned to Paris after his release.

The Arcade Gallery in London gave him his first UK show in 1946 and in 1948 he lived in both England and Scotland and exhibited in Edinburgh and Glasgow. He showed in Britain again, including as part of the mixed show 'Recent Trends in Realist Painting' at the ICA in 1952, as well as the USA and Israel after his first Paris exhibition in 1953. In 1970 he travelled to Venice and Rome on a painting tour. Grégoire Michonze died in Paris, France on 29 December 1982. The Musée d'Art moderne in Troyes held a major retrospective of his work in 1985.