Karan Singh was born in a royal Rajput family, Singh was educated at Doon School, Dehra Dun, and received a B.A. degree from Jammu and Kashmir University, Srinagar, and subsequently an M.A. degree in Political Science and a PhD degree from Delhi University.
While he was just 18, he was appointed as the regent of Jammu and Kashmir state after his father stepped down as the ruler, following the state's accession to India. He served successively as regent, the first and last Sadr-i-Riyasat, and governor of the state of Jammu and Kashmir from 1965 to 1967. In 1967, he resigned as Governor of Jammu and Kashmir, and became the youngest-ever member of the Union Cabinet, holding the portfolios of Tourism and Civil Aviation. In 1973, he became the Minister for Health and Family planning, serving in this post until 1977.
From 1967 to 1984 Karan Singh was a member of the Lok Sabha. In 1984, he contested the Lok Sabha polls as an independent candidate from Jammu but lost the election. He was a member of the Rajya Sabha first representing J&K National Conference – a Muslim dominated state party active in northern Indian state of Jammu & Kashmir – from 30 November 1996 to 12 August 1999 and currently is a Rajya Sabha member from 28 January 2000 representing INC. He has served as Chancellor of Banaras Hindu University, Jammu and Kashmir University, Jawaharlal Nehru University, and NIIT University.
He is a poet and authored poetry book too and his poems featured in the poetry anthology, The Dance of the Peacock: An Anthology of English Poetry from India, featuring 151 Indian English poets, edited by Vivekanand Jha and published by Hidden Brook Press, Canada.