John Kennedy, 8th Earl of Cassilis (April 1700 – 7 August 1759)[1] was a Scottish peer.
He succeeded to the titles of 10th Lord Kennedy and 8th Earl of Cassilis on 23 July 1701.
His paternal grandparents were John Kennedy, 7th Earl of Cassilis.
Her elder sister became Anne Hamilton, 2nd Countess of Ruglen.
On the death of the 8th Earl, a competition arose, both for the estates and for the title of Earl of Cassilis, between William, Earl of March and Ruglen, heir general, and Sir Thomas Kennedy of Culzean, 4th Baronet, the heir male.