Mirko was born in Udine, Italy on September 28, 1910, the second of three brothers (Dino was the eldest, and Afro the youngest).

Dino, Mirko and Afro later attended the Institute of Applied Arts in Monza, where they studied under the sculptor Arturo Martini.

[1][2] In 1934, Mirko moved to Rome, where he held his first solo exhibition in 1936 at the Galleria della Cometa.

[1][3] In the same year he exhibited his work at the Venice Biennale, together with other artists associated with the so-called Scuola Romana (including Giuseppe Capogrossi, Alberto Ziveri, Guglielmo Janni and Renato Guttuso).

In 1957, he moved to Cambridge, Massachusetts where Josep Lluís Sert appointed him to direct the Design Workshop at Harvard University; Mirko stayed there until 1963, when he joined Eduard Sekler and Robert Gardner in the newly-created Department of Visual and Environmental Studies.