Sir William de Thorpe (died 27 May 1361) was an English lawyer who was Chief Justice of the King's Bench from 26 November 1346 to 26 October 1350.

As a clerk of this court, he was assaulted on one occasion in 1318, when his enemies allegedly urinated on him.

He was knighted in 1345, at the same time as he was made justice of the King's Bench.

Thorpe accumulated great estates, particularly in Lincolnshire, and his wealth must have derived primarily from bribes and maintenance.

In 1357, he was excommunicated for non-appearance at the trial of Thomas de Lisle, Bishop of Ely, in Avignon.