Charles Owen O'Conor, O'Conor Don PC (Irish: Cathal Eóghan Ó Conchubhair Donn; 7 May 1838 – 30 June 1906), was an Irish MP of the United Kingdom.
The eldest son of Denis O'Conor, Charles O'Conor was educated at Downside School in England and became a Liberal MP for Roscommon from March 1860 until defeated in 1880. He was an unsuccessful candidate for Wexford in 1883. He was appointed High Sheriff of Sligo for 1863 and High Sheriff of Roscommon for 1884.
He was also President of the Society for the Preserving the Irish Language, a precursor of the Gaelic League. He wrote a history of his family called "The O'Conors of Connacht".
He married twice; firstly Georgina Mary, the daughter of Thomas Perry, with whom he had four sons, and secondly Ellen Letitia, the daughter of John Lewis More O'Ferrall, of Co. Longford.