Luton Castle was a 12th-century castle in the town of Luton, in the county of Bedfordshire, England (). It was a timber motte-and-bailey structure built in 1139 and demolished in 1154. In 1963, the bailey was exposed, but not excavated. An excavation was done in 2002, revealing a steep ditch. The site is now home to Matalan, a discount store. Nothing visible remains of the castle.