Cearbhall Ó Dálaigh (12 February 1911 – 21 March 1978; Irish pronunciation: [ˈcaɾˠwaɫ̪ oː ˈdˠaːɫ̪i]) served as the fifth President of Ireland, from 1974 to 1976. He resigned in 1976 after a clash with the government. He also had a notable legal career, including serving as Chief Justice of Ireland.

Cearbhall Ó Dálaigh, one of four children, was born on 12 February 1911, in Bray, County Wicklow. His father was a shopkeeper with little interest in politics.

Cearbhall had an older brother; Aonghus, and two younger sisters; Úna and Nuala. He went to St. Cronan's Boys National School. and later to Synge Street CBS in Dublin. While attending University College Dublin, he became auditor of An Cumann Gaelach and of the Literary and Historical Society. He also became Irish language editor of the Irish Press.

A graduate of University College Dublin, Ó Dálaigh was a committed Fianna Fáil supporter who served on the party's National Executive in the 1930s, he became Ireland's youngest Attorney General in 1946 under Taoiseach Éamon de Valera, serving until 1948. Unsuccessful in Dáil Éireann and Seanad Éireann elections in 1948 and 1951, he was re-appointed as Attorney General in 1951 and in 1953 he was appointed as the youngest member of the Supreme Court by his mentor, de Valera. Less than a decade later, he became Chief Justice, when selected by then Taoiseach, Seán Lemass. He was a keen actor in his early years and became a close friend of actor Cyril Cusack. It is commonly stated that Ó Dálaigh and Cusack picketed the Dublin launch of Disney's Darby O'Gill and the Little People, for what they felt was the film's stereotyping of Irish people. However, there is no contemporary reference of this ever occurring.