De Masi is an Italian surname. Notable people with the surname include:
Arianna De Masi (born 1999), Italian sprinter Domenico De Masi (1938–2023), Italian sociologist Fabio De Masi (born 1980), German politician of Italian descent Francesco De Masi (1930–2005), Italian conductor and film score composer Piero De Masi (1937–2021), Italian ambassador
See also Lance de Masi (born 1949), former president of the American University in Dubai Giuseppe Di Masi (born 1981), Italian football player and coach
it:De Masi