John Denny Vesey, 1st Baron Knapton (died 1761) was an Anglo-Irish politician and peer.
Vesey was the son of Sir Thomas Vesey, 1st Baronet and Mary Muschamp. In 1727 he was elected to the Irish House of Commons as the Member of Parliament for Newtownards, holding the seat until 1750. On 6 August 1730 he succeeded to his father's baronetcy. On 10 April 1750 he was elevated to the peerage as Baron Knapton, in the Queen's County, in the Peerage of Ireland, and he assumed his seat in the Irish House of Lords.
He married Elizabeth Brownlow, daughter of William Brownlow. He was succeeded in his titles by his eldest son, Thomas Vesey, who was made Viscount de Vesci in 1776.