Rear Admiral John Townshend, 4th Marquess Townshend (28 March 1798 – 10 September 1863), known as John Townshend until 1855, was a British nobleman, peer, politician, and naval commander.

Townshend was the son of Lord John Townshend, younger son of George Townshend, 1st Marquess Townshend. His mother was Georgiana Anne Poyntz. He served in the Royal Navy and achieved the rank of Rear-Admiral. Between 1847 and 1855 he also sat as a Member of Parliament (MP) for Tamworth. In the latter year he succeeded his first cousin in the marquessate and entered the House of Lords.

Lord Townshend married Elizabeth Jane Crichton-Stuart, daughter of Lord George Stuart, younger son of John Crichton-Stuart, 1st Marquess of Bute, on 18 August 1825. They had five children:

• Lady Audrey Jane Charlotte Townshend (d. 1926), married firstly, Greville Howard, son of Charles Howard, 17th Earl of Suffolk and had issue. She married secondly, General Redvers Henry Buller.
• James Dudley Browlow Stuart Townshend (d. 1846), unmarried
• Anne Maria Townshend (d. 1899), married Alexander Sherson
• Elizabeth Clementina Townshend (d. 1910), married John St Aubyn, 1st Baron St Levan and had issue
• John Villiers Stuart Townshend, 5th Marquess Townshend (1831–1899)

Lord Townshend died in September 1863, aged 65, as result of a fall from his horse in the grounds of his home, Raynham Hall, and was buried at East Raynham, Norfolk.^[1] He was succeeded in his titles by his eldest son John. Lady Townshend died in 1877.

• O'Byrne, William Richard (1849). "Townshend, John" . A Naval Biographical Dictionary . John Murray – via Wikisource.

• Kidd, Charles, Williamson, David (editors). Debrett's Peerage and Baronetage (1990 edition). New York: St Martin's Press, 1990, ^{[page needed]}
• Leigh Rayment's Peerage Pages ^{[self-published source] [better source needed]}
• Leigh Rayment's Historical List of MPs
• Lundy, Darryl. "FAQ". The Peerage.^{[unreliable source]}

• Hansard 1803–2005: contributions in Parliament by the Marquess Townshend