Sir William Twysden, 3rd Baronet (11 December 1635 – 27 November 1697), of Roydon Hall in Kent, was an English landowner and Member of Parliament.
He was the eldest son of Sir Roger Twysden, 2nd Baronet, and succeeded to the baronetcy on 27 June 1672.
He entered Parliament in 1685 as member for Kent, and subsequently also represented Appleby, and was elected for New Romney although he never sat for the constituency.
He married Frances Cross, daughter of Josiah Cross, and they had ten children including Sir Thomas Twysden, 4th Baronet (c. 1676-1712) and Sir William Twysden, 5th Baronet (1677-1751).