Constantin Agiu (November 5, 1891, Dolj County – February 19, 1961, Gura Humorului) was a Romanian Communist politician; he was also President of the Great National Assembly, the unicameral legislature of the Romanian People's Republic.

[citation needed] During World War II, together with Foriș, Remus Koffler, Iosif Rangheț, Constantin Pîrvulescu, and Lucrețiu Pătrășcanu, he belonged to the small clandestine party faction that was active inside Romania.

[1] Even after April 4, 1944 (when Foriș was removed from the office of general secretary), he held important positions.

For example, he was in charge of revenue control by the Central Financial Commission of the PCR, or conducting negotiations with the PSD for the realization of the Unique Workers' Front.

In 1958, he joined the leadership committee of the Association of Former Inhabitants and deported anti-fascist politicians.