Mathern Palace is a Grade I listed building in the village of Mathern, Monmouthshire, Wales, located some 3 miles (4.8 km) south-west of Chepstow close to the Severn Estuary. Between about 1408 and 1705 it was the main residence of the Bishops of Llandaff. After falling into ruin, it was restored and its gardens laid out between 1894 and 1899 by the architectural writer Henry Avray Tipping.