William Cavendish, 2nd Earl of Devonshire (c. 1590 – June 20, 1628) was the son of William Cavendish, 1st Earl of Devonshire.

He was the patron of Thomas Hobbes, who took him on the 'Grand Tour' around Europe between 1610 and 1615.

He married Christian Bruce, daughter of Edward Bruce, 1st Lord Kinloss, on 10 April 1608. They had three children:

• Anne Cavendish (c. 1611–?), married Robert Rich, 3rd Earl of Warwick and had issue.
• William Cavendish, 3rd Earl of Devonshire (1617–1684)
• Charles Cavendish (c. 1628–?)