Captain Lockhart Leith (2 June 1876 – 30 November 1940) was a British fencer and Royal Navy officer.
He competed in the individual sabre event at the 1908 Summer Olympics.Leith was the son of Walter Leith of Ashby-de-la-Zouch.
He was educated at Burney's Royal Naval Academy, Gosport and joined HMS Britannia in 1890.
He was promoted to lieutenant on 30 September 1898, and among his early postings was a temporary posting to HMS Duke of Wellington in 1902.
He was promoted to commander on 31 December 1910 and captain on 31 December 1916.Leith served with distinction during the First World War.
He was awarded the Distinguished Service Order in 1917 and appointed a Companion of the Order of St Michael and St George in the 1919 New Year Honours.