Sir Robert Long, 6th Baronet (1705 – 10 February 1767) was an English politician.
The only surviving son of Sir James Long, 5th Baronet and his wife Henrietta Greville, Long was baptised on 8 November 1705 at St Martin in the Fields, Westminster, London. Educated at Balliol College, Oxford, he succeeded his father as 6th Baronet on 16 March 1729, and inherited the family estates, including the manors of Draycot and Athelhampton.
He was elected Member of Parliament for the rotten borough of Wootton Bassett in 1734, and for Wiltshire in 1741.
He married on 29 May 1735 at Woodford, Essex, Emma Child, the daughter of Richard Tylney, 1st Earl Tylney, of Wanstead (said to be possessed of 'almost revolting wealth'), and his wife Dorothy Glynn.
Sir Robert and Emma had two daughters and four sons including:
Many letters written by Sir Robert to his wife are held in the Wiltshire and Swindon Record Office, and furnish a picture of a happy marriage in the eighteenth century, illustrating a genuine affection for his wife, and fatherly love for his children, with nicknames such as 'Jemmy' and 'Dolly'. He had good-natured relationships with his dependants, even going so far as choosing material for a new dress for Lady Emma's companion.
Sir Robert Long died on 10 February 1767 and was buried at Draycot. His wife died on 8 March 1758.