Sir John Arundell IV, born at Treleigh Manor , in the parish of St Ervan, Cornwall in about 1340 was an English knight and as son of John Arundell (III) was heir to a family that held large amounts of land in Devon and Cornwall.

He died on 5 November 1376, drowned off the coast of Ireland, in a fleet going to Brittany.

[1] Sir John Arundell IV married Joan Luscote, the daughter of Sir William Luscote, in about 1370.

His wife survived him and married, as her second husband, widower Sir William Lambourne.

[2] John and Joan's son and heir, Sir John Arundell (V), married Annora Lambourne, his step-father's daughter by a previous wife.