He married, firstly, 30 March 1231, Isabel Marshal, widow of Gilbert de Clare, Earl of Gloucester and Hertford, and daughter of William Marshal, 1st Earl of Pembroke. She died in childbed 17 January 1240.
He married secondly, 23 November 1243, Sanchia of Provence, daughter of Raymond Berengar V, comte de Provence. She died 9 November 1261.
He married, thirdly, 16 June 1269, Beatrice de Falconburg, daughter of Dirk II, Count of Falconburg.
He had four children by his first wife and two sons by second wife, but none of these had children; his only descendants are via his illegitimate son (Richard de Cornwall) by Joan de Vautort (or Valletort).
He was buried at Hayles Abbey, which he had founded.