O.N.V Kurup was born to O. N. Krishna Kurup and K. Lakshmikutty Amma, on May 27, 1931 at Chavara, Kollam in Kerala. He lost his father when he was eight. His childhood days were spent in the village where he attended the public 'Government School, Chavara'. After graduating with a bachelor's degree in Economics from SN College, Kollam, he moved to Thiruvananthapuram city (Trivandrum) where he joined Travancore University (now Kerala University) and pursued Master of Arts (postgraduate) in Malayalam literature.
O.N.V. was a lecturer at Maharajas College – Ernakulam, University College – Trivandrum, Arts and Science College – Kozhikode, and Brennen College – Thalassery. He joined Government Women's College – Trivandrum as the Head of Malayalam Department. He was also a visiting professor at Calicut University. He retired from service in 1986.
He received the Jnanpith Award, India's highest literary honour, for the year 2007. He is the fifth Jnanpith laureate from Kerala and the second Malayalam poet to win the prestigious award. According to a statement by Bharatiya Jnanpith, the trust which presents the award, Kurup began his career as a "progressive writer and matured into a humanist though he never gave up his commitment to socialist ideology". He is now settled at Vazhuthacaud in Thiruvanathapuram, with his wife Sarojini. His son Rajeev works with the Indian Railways Authority, and daughter Dr.Mayadevi is a noted gynaecologist in Durham, United Kingdom. Malayalam playback singer Aparna Rajeev is his granddaughter.