Born in Meda (Monza) in 1904, he received his degree in architecture from the Milan Polytechnic.
In 1926 he was one of the founders of the "Group of Seven", signing with other architects - including A. Libera and G. Pollini - the first document of the Italian Rationalism.
In 1928 he took part in the first Exposition of Rationalist Architecture in Rome, presenting some projects reminding to constructivism and futurism. Active as painter as well, Terragni took care of the “Exhibition of Fascist Revolution” in 1932. Futurism, Constructivism and Rationalism were the guidelines of his architecture, of which the “Casa del Fascio (1932-36)” in Como represents one of his best examples.