Windham Henry Quin, 2nd Earl of Dunraven and Mount-Earl (29 September 1782 – 6 August 1850) was an Irish Peer.
The eldest son of Valentine Richard Quin, 1st Earl of Dunraven and Mount-Earl, he was styled Lord Adare from 1816 to 1822 and Viscount Adare thereafter until he succeeded to the Earldom on the death of his father in 1824. He took the additional surname of Wyndham, becoming Windham Wyndham-Quin, on 7 Apr. 1815.
He was appointed Custos Rotulorum of County Limerick for life in 1818. He served as an MP for County Limerick in the Parliament of the United Kingdom from 1806 to 1820.
On 27 December 1810 he married Caroline, daughter and heiress of Thomas Wyndham of Dunraven Castle, Glamorgan and Clearwell, Gloucestershire. They had the following children: