St Mary's Lifeboat Station is situated in St Mary's Harbour, Isles of Scilly and has been an important station for the Royal National Lifeboat Institution since the service began in 1837, however without a service between 1855 and 1874.

The 46 ft 9in Watson-class lifeboat was a non self-righting displacement hull lifeboat built between 1947 and 1956 and operated by the Royal National Lifeboat Institution between 1947 and 1989.