Sir Thomas Arundell of Wardour Castle in Wiltshire was a Cornish administrator and alleged conspirator.

Wardour Castle or Old Wardour Castle is a ruined 14th-century castle at Wardour, on the boundaries of the civil parishes of Tisbury and Donhead St Andrew in the English county of Wiltshire, about 15 miles (24 km) west of Salisbury. The castle was built in the 1390s, came into the ownership of the Arundells in the 16th century, and was rendered uninhabitable in 1643 and 1644 during the Civil War. A Grade I listed building, it is managed by English Heritage and open to the public.