William Henry Dawnay, 7th Viscount Downe (15 May 1812 – 26 January 1857) was a British politician.
Downe was returned to Parliament as one of two representatives for Rutland in 1841, a seat he held until 1846.
However, as this was an Irish peerage it did not entitle him to a seat in the House of Lords.
Lord Downe married Mary Isabel, daughter of the Right Reverend Richard Bagot, in 1843.
Lord Downe, his wife and her second husband, are buried in the churchyard of the Church of St James, Baldersby in North Yorkshire.