Thomas Laycock (1786 – 7 November 1823) was an English soldier, explorer, and later businessman, who served in North America during the War of 1812, but is most famous for being the first European to travel overland through the interior of Tasmania (then known as Van Diemen's Land).

Whilst the details of his birth are unknown, it is known that he was baptised in London, and arrived in Sydney as a nine-year-old with his mother on 21 September 1791 aboard HMS Gorgon, as part of the Third Fleet.

After service in both Sydney and Norfolk Island, Laycock was sent to Port Dalrymple, Van Diemen's Land to serve under Captain Anthony Fenn Kemp in 1806.

Following a more easterly route on their northward journey, the party found the going much easier, riding up through the Midlands that was to become the major pastures and farmland of the colony in the following decade.

Upon his return to Sydney, Laycock discovered that the Rum Rebellion was in full-swing, and the New South Wales Corps, under the leadership of Major George Johnston, and former soldier turned pastoralist John Macarthur had enacted a military coup and had arrested Governor William Bligh.

Laycock was appointed to the criminal court that tried Macarthur for his involvement in the plot, and in so doing, he became the only physical casualty of the bloodless rebellion, when he was sent to search Government House for evidence, and fell through a manhole.

Following Macquarie's arrival, the newly married Laycock departed from New South Wales with wife Isabella, aboard HMS Dromedary on 18 March 1810, sailing for England.

The New South Wales Corps were disbanded in disgrace following their part in the rebellion, and most of the men transferred into a newly formed 102nd Regiment of foot, and were recalled to England.