Robert Cornewall (1647 – 1705) was an English soldier and courtier.
He was born in 1647, the eldest son of Humphrey Cornewall and Theophila Skynner, and was baptised at Eye, Herefordshire on 17 June 1647.
He joined the army, becoming an Ensign in Lord Worcester's regiment on 13 June 1667, and a Captain in Sir John Talbot's Dragoons on 22 February 1678. He was made captain of an independent troop on 18 June 1685, Captain lieutenant in the Queen Dowager's Horse on 31 July 1685, and captain in 1687.
He was elected to represent Leominster in the general election of 1685, a post that his father had occupied previously. He was also a magistrate in Herefordshire between 1675 and 1689; Commissioner for Assessment from 1677 to 1680 and in 1689; a freeman of Ludlow in 1681 and captain of the Herefordshire Militia from 1683 to 1689. He was gentleman waiter to Prince George of Denmark from 1683 to 1689.
Identified as a Jacobite after the Glorious Revolution, he lost his commission and his court appointments. An attempt to return to public life on the accession of Queen Anne was unsuccessful.
He married Edith Cornewallis, daughter of Sir Francis Cornewallis of Abermarlais, Carmarthenshire, in July 1668. The couple had eleven children: