Casas de Reina is a municipality in the province of Badajoz, in the autonomous community of Extremadura, Spain. It is a small rural settlement in the south of the province, within the comarca of Zafra-Río Bodión.
The municipality is sparsely populated. According to the 2005 census conducted by Spain's National Statistics Institute (INE), Casas de Reina had a population of 193 inhabitants. Like many villages in this part of Extremadura, it is characterised by a small, ageing population and an economy historically tied to agriculture.
Its main claim to fame is the Roman archaeological site of Regina Turdulorum, whose remains lie within the municipal area. The site preserves the ruins of a Roman town, including elements of its urban layout, and is the principal heritage attraction associated with Casas de Reina.