Dyffryn, often Duffryn, is a village in the communities of Wenvoe and St Nicholas and Bonvilston, in the Vale of Glamorgan in south Wales.

Dyffryn House and its Edwardian garden are Grade I listed buildings and are leased to the National Trust.

[2] The 22 hectare (55 acre) landscaped gardens were designed by Thomas Mawson between 1894 and 1909, and are the largest and "most exotic" in Glamorgan.

[5] The 1811 Topographical Dictionary of Wales simply said "DYFFRYN, in the Cwmwd of Is Caeth, Cantref of Brenhinol (now called the Hundred of Dinas Powys), Co. of Glamorgan, South Wales; in the Parish of St. Nicholas.

Near Dyffryn House, which is the Property of The Honourable William Booth Grey, are several Druidical Monuments.