[1] Colombo was born in Albiate, province of Monza and Brianza, Lombardy.

[1] He worked as a trade unionist prior to entering politics among the ranks of the Christian Democracy.

[3][4] He served in the cabinet of Prime Ministers Mariano Rumor (1974), Giulio Andreotti (1976–1979) and Cossiga (1979–1980).

He served as Minister of Health in the Government of Italy from March to November 1974.

[3][6] He was an important figure in Chinese-Italian relations,[4] he founded the Italian Chinese Institute and the Italy China Foundation, the latter of which he presided over.