Guy Pierre Kersaint (1747–1822) was a French sailor, the brother of the sailor and politician Armand-Guy-Simon de Coetnempren, comte de Kersaint. He took part in the American war of independence.
He did not accept the principles of the French Revolution, so he emigrated. He was restored to his rank in the French Navy in 1803, and died in 1822, after having been prefect maritime of Antwerp, and prefect of the départment of Meurthe.