Sir Robert Bankes Jenkinson, 4th Baronet (24 January 1687 – 2 July 1738), was a British lawyer and politician who sat in the House of Commons from 1717 to 1727. Jenkinson was the second son of Sir Robert Jenkinson, 2nd Baronet, and his wife Sarah Tomlins, daughter of Thomas Tomlins of Bromley, Middlesex, and was baptised on 24 January 1687. He matriculated at Trinity College, Oxford, on 18 February 1703. He was admitted at Lincolns Inn in 1705 and was called to the bar in 1713. He succeeded his brother Sir Robert Jenkinson, 3rd Baronet, on 29 October 1717. He married Catherine Dashwood, daughter of Sir Robert Dashwood, 1st Baronet, MP of Northbrook, Oxfordshire, on 12 June 1718.