Constantine (Konstantinos) Karamanlis (Κωνσταντίνος Καραμανλής) (March 8, 1907 - April 23, 1998) is a towering figure of modern Greek politics and history.

He was born in the town of Proti, in the region of Serres in northern Greece. His father was Georgios Karamanlis, who fought during the national struggle of the Greeks in Macedonia, in 1904-1908. After spending his childhood in Macedonia, he went to Athens to complete his degree in Law. He practiced law in Serres and was elected as member of parliament for the first time at the age of 28. Karamanlis quickly rose through the ranks of Greek politics eventually becoming Minister of Public Works for the Papagos government. He performed unusually well in this position and when Papagos was to be succeeded King Paul of Greece immediately suggested the young Karamanlis for Prime Mininster. He first became prime minister in 1955 securing an absolute parliamentary majority in three successive elections (1955, 1958 and 1961). In 1959 he announced a five-year plan (1960–64) for the Greek economy, emphasizing improvement of agricultural and industrial production.

In July 1963, he resigned the premiership after a disagreement with King Paul of Greece, and spent four months abroad. In November, the National Radical Union (ERE), under his leadership, was defeated in the general election. Karamanlis left Greece after realising that the conditions necessary for him to continue his work no longer existed. He spent the next 11 years in exile in Paris France.

Throughout his exile in France, Karamanlis was only a vocal opponent of the military junta that seized power in Greece in April 1967. After the fall of the junta in July 1974, he returned to Athens as prime minister following huge public support mainly because he was considered the only solution available. He formed a government of National Unity in order to deal immediately with the Cyprus crisis and to restore democratic institutions in Greece. He legalized the Communist Party of Greece (KKE) but he didn't abolish censorship and he was very indulgent with the members of the 1967 coup who still maintained main positions in police and army.

Karamanlis founded a new conservative party, New Democracy, and served as prime minister until 1980. The Greek Parliament then elected him President of the Republic, where he served until 1985. He oversaw Greece's entry (1981) into the European Community (now the European Union). In 1990 the New Democracy government of Constantine Mitsotakis re-appointed him President, and he served until 1995, when he was succeeded by Costis Stephanopoulos. Karamanlis retired from political life in Greece in 1995, at the age of 88 years old, having spent more than sixty years in active politics.

Constantine Karamanlis died after a short illness in 1998, at the age of 91.

His nephew Costas Caramanlis is now leader of the New Democracy party, and Prime Minister as of March 7, 2004.