Italian sculptor who was active between the World Wars. He is known for figurative sculptures executed in a wide variety of styles and materials.

Martini was trained in goldsmithing and in ceramics and worked for a time as a potter. In 1905 he began sculpting; he attended art classes in Italy at Treviso and Venice before traveling to Munich, Germany, where he studied under the academic sculptor Adolf von Hildebrand (Hildebrand, Adolf von) in 1909. Martini experimented with an angular and emotional Expressionist (Expressionism) style in his early works (such as The Prostitute, 1909). He first exhibited his sculptures in Paris in 1912.

In 1921 Martini became involved with the art journal Valori plastici (“Plastic Values”), which advocated a return to Classical traditions, and his sculpture subsequently became more naturalistic (as in A Boy's Head, 1923). In 1931 he won the grand prize for sculpture at the first Quadriennale in Rome.

Martini's works range from delicate terra-cottas such as Moonlight (1932) to dramatic figures in stone such as Thirst (1934). The large and ambitious high relief for the Palace of Justice in Milan, Corporate Justice (1937), is perhaps the pinnacle of his achievement. Martini was particularly adept at conveying the tension and movement of physical activity, as in Woman Swimming Under Water (1941). In 1945 he published a pamphlet, Sculpture: A Dead Language, in which he expressed his frustration with the limitations of the medium.