Thomas Conolly (Leixlip Castle, 1738 – 27 April 1803 Celbridge) was an Irish landowner and Member of Parliament.

Conolly was the son and heir of William James Conolly (d. 1754) of Castletown House, County Kildare, Ireland, by his wife Lady Anne Wentworth, daughter of Thomas Wentworth, 1st Earl of Strafford (1672–1739).

[2] In 1761 he was elected to the Parliament of Ireland for Ballyshannon and for County Londonderry, sitting for the latter constituency until May 1800.

[6] The Conolly summer residence 'Cliff House' on the banks of the River Erne between Belleek, County Fermanagh and Ballyshannon, County Donegal was demolished as part of the Erne Hydroelectric scheme, which constructed the Cliff and Cathaleen's Fall hydroelectric power stations.

Wentworth House, 5, St James's Square, Conolly's London townhouse,[7] built by his uncle William Wentworth, 2nd Earl of Strafford (1722–1791), became the property of his nephew George Byng (1764–1847), the son of his sister Anne Conolly, whose younger brother was Field Marshal John Byng, 1st Earl of Strafford (1772-1860), elevated to the peerage in 1847 with the same territorial designation as the earldom of his maternal cousins, which earldom had become extinct in 1799.