James Tuchet, 3rd Earl of Castlehaven (c. 1617 - 11 October 1684) was the son of Mervyn Tuchet, 2nd Earl of Castlehaven and his first wife, Elizabeth Barnham (1592 - c. 1622).

He succeeded his father as Earl of Castlehaven and Baron Audley of Orier on 14 May 1631, when his father was attainted and beheaded.

He was created Baron Audley of Hely with remainder "to his heirs forever" on 3 June 1633, with place and precedency of George, his grandfather, formerly Baron Audley, in an effort to nullify his father's attainder. However, this was considered insufficient, legally, until a bill was passed by Parliament in 1678 allowing him to inherit the original Barony of Audley.

Castlehaven was involved in the defence of Ireland during the Cromwellian invasion. He was not a noteworthy commander, although along with Ulick Burke he won a small victory, the battle of Tecroghan in June 1650.

He married twice, first Elizabeth Brydges, daughter of Grey Brydges, 5th Baron Chandos and of his wife Lady Anne Stanley (1580-1647), who married the 2nd Earl of Castlehaven after Lord Chandos' death. (Anne Stanley was thus both the 3rd Earl's stepmother, and his mother-in-law.) He married secondly, about 19 June 1679, Elizabeth Graves.

He died sine prole 11 October 1686, at Kilcash, County Tipperary, Ireland and was succeeded in the Earldom by his brother.