Léon Zack (1892–1980), also known as Lev Vasilyevich Zak (Russian: Лев Васильевич Зак), was a Russian-born French figurative and later abstract painter and sculptor.

Léon Zack was born into a Jewish family in Nizhny Novgorod in Russia on 12 July 1892, to a pharmacist father.

[5] After leaving Russia in 1920, he spent time in Florence, Rome and Berlin, before settling in Paris in 1923.

[8] In 1926, Zack had his first one-man show in Paris, painting figures including harlequins and gypsies.

Around this time Zack's work abandoned figuration for geometrical abstraction, gradually moving toward a more expressive mode of Tachisme.