St Just, also known as St Just in Penwith, is a town and civil parish in the Penwith district of Cornwall, England, United Kingdom. It lies along the B3306 road which connects St Ives to the A30 road. The parish encompasses the town of St Just and the nearby settlements of Trewellard, Pendeen and Kelynack: it is bounded by the parishes of Morvah to the north-east, Sancreed and Madron to the east, St Buryan and Sennen to the south and by the sea in the west.