William Watkin Edward Wynne (23 December 1801 – 9 June 1880) was a Welsh Member of Parliament and antiquarian.
Wynne was born on 23 December 1801 in Denbighshire, Wales and educated at Westminster School and Jesus College, Oxford.
He was Conservative Member of Parliament for Merioneth from 1852 to 1865. He also served as High Sheriff of Merionethshire in 1867 and became constable of Harlech Castle in 1874.
He inherited a collection of manuscripts in 1859, known as the Hengwrt collection, from his kinsman Sir Robert Williames Vaughan. The collection had been assembled by the 17th-century antiquarian Robert Vaughan and it contained an early version of the Canterbury Tales, mystery plays in Cornish and many early Welsh manuscripts, including twelve manuscripts of the Welsh laws of Hywel Dda. Wynne catalogued the manuscripts, publishing the result in Archaeologia Cambrensis between 1869 and 1871, and allowed scholars to examine and copy them.
Wynne had considerable knowledge about the history and genealogy of north Wales, assisting other writers and contributing articles on Merionethshire to Archaeologia Cambrensis and elsewhere. He also wrote a history of Harlech Castle in 1878. He died on 9 June 1880.