Romanian politician, head of the Liberal Party, and one of the leaders of that party's opposition to the communist ascendancy in Romania after World War II.

The son of the great 19th-century statesman Ion Brătianu and a parliamentary deputy from 1895, Constantin Brătianu held no government position until 1933–34, when he served as minister of finance. After the assassination of the Liberal premier Ion Duca in December 1933, he acceded to the leadership of the Liberal Party. Through the following years he opposed the dictatorial course of King Carol II and the compromising politics of the king's premier, Gheorghe Tătărescu.

During World War II, under the pro-Axis military dictatorship of Ion Antonescu (Antonescu, Ion), Brătianu initially supported the government's war policy against the Soviet Union; but, after the recovery of Romanian territory from the Soviets, he turned against the Antonescu regime and helped plot the successful antifascist coup of Aug. 23, 1944. He subsequently served as minister without portfolio in two noncommunist liberation cabinets but refused appointment in the leftist regime of Petru Groza in March 1945. Brătianu's pro-Western, anti-Soviet position won him the enmity of the communists, and, after the full communist accession to power, he was arrested and imprisoned without trial. He died in prison.