Robert John Le Mesurier McClure (or M'Clure) (28 January 1807 - 17 October 1873) was a British explorer of the Arctic.
He was born at Wexford, in Ireland, the posthumous son of one of Abercrombie's captains. and spent his childhood under the care of his godfather, General Le Mesurier , governor of Alderney, by whom he was educated for the army. He entered the navy, however, in 1824, and twelve years later gained his first experience of Arctic exploration as mate of HMS Terror in the expedition (1836-1837) commanded by Captain (afterwards Sir) George Back .
On his return he obtained his commission as lieutenant, and from 1838 to 1839 served on the Canadian lakes , being subsequently attached to the North American and West Indian naval stations, where he remained till 1846. Two years later he joined the Franklin search expedition (1848-1849) under James Clark Ross as first lieutenant of Enterprise, and on the return of this expedition was given the command of Investigator in the new search expedition (1850-1854) which was sent out by way of Bering Strait to co-operate with another from the north-west. In the course of this voyage he achieved the distinction of completing (1850) the work connected with the discovery of a North-West Passage. On his return to England, McClure was awarded gold medals by the English and French geographical societies, was knighted and promoted to post-rank, his commission being dated back four years in recognition of his special services.
From 1856 to 1861 he served in Eastern waters, commanding the division of the naval brigade before Canton in 1858, for which he received a CB in the following year. His latter years were spent in a quiet country life; he attained the rank of rear-admiral in 1867, and of vice-admiral in 1873.
McClure Strait was later named after him.
- Admiral Sherard Osborn , The Discovery of a North-West Passage (1856).