General Robert Manners (2 January 1758 – 9 June 1823) was a British Army officer and Member of Parliament.
He was the eldest son of General Lord Robert Manners by his wife Mary Digges, and succeeded to his father's estate at Bloxholm in Lincolnshire. He was educated at Caen and took the Grand Tour.
He joined the Army as a Cornet in the 3rd Dragoons in 1778, and became a Captain in the 86th Foot in 1779 and a Major in the 80th Foot on 28 December 1782. On 19 March 1783 he was made an equerry to the King and on 24 April 1784 was promoted to Lieutenant-Colonel in the 1st Battalion 84th Regiment of Foot. In the general election of that year he was elected to Parliament for Great Bedwyn through the influence of Lord Ailesbury, the expenses of the election (£2500, or the equivalent of £276000 today) being paid by George Rose out of Government secret funds. After a period on half-pay, he joined the 3rd Foot Guards as Captain-Lieutenant and Lieutenant-Colonel on 24 February 1787. He was considered as a replacement for Sir Henry Peyton, MP for Cambridgeshire, on that gentleman's death in 1789, but unsuccessfully stood at Northampton in the general election in 1790.