Carlo Donat-Cattin (26 June 1919 – 17 March 1991) was an Italian politician and trade unionist.

He was leader of the internal left current of the DC Forza Nuove (New Forces).

During World War II, he fought with the "White faction" (Christian-Democrat) of the Italian resistance movement.

Donat-Cattin was initially in favour of dialogue towards DC's historical rival, the Italian Communist Party (Italian: Partito Comunista Italiano, or PCI), but after 1979 he became a supporter of the preambolo theory, which aimed to exclude PCI from any state charge.

In 1980, however, after his son Marco was discovered to be a member of the far-left terrorist formation Prima Linea,[2] he abandoned any public position and left politics for a while.