Sir William Glynne, 1st Baronet (20 January 1638 – 8 September 1690) was a Welsh politician.
William was the son of Sir John Glynne, the Lord Chief Justice during the Commonwealth. He was educated at Jesus College, Oxford, taking his degree in 1656, and represented Caernarfon in the Third Protectorate Parliament. Both Sir John and his son went over to the cause of Charles II at the Restoration. William was again returned for Caernarfon during the Convention Parliament, and was subsequently created a baronet, of Bisseter, Oxfordshire, on 20 May 1661.
In 1666, Sir William inherited the estate of Hawarden, Flintshire, from his father, and served as High Sheriff of Flintshire in 1673. By his wife Penelope Anderson, Glynne had two sons:
| Parliament of England | ||
|---|---|---|
| Preceded by Unknown |
Member of Parliament for Caernarfon 1660–1661 |
Succeeded by William Griffith |
| Baronetage of England | ||
| New title | Baronet (of Bisseter, Oxfordshire) 1661–1690 |
Succeeded by William Glynne |