Thwaite Mills is an industrial museum in Leeds, West Yorkshire, England. It is a fully restored working water-powered mill built in 1823-25, harnessing the power of The River Aire, and claims to be "one of the best last remaining examples of a water-powered mill in Britain." It is administered by Leeds City Council. The mill, the manager's house, and three associated buildings are all grade 2 listed buildings.
The first known mill on the site was a fulling mill built in 1641, as part of the local industry of manufacturing woollen cloth. In 1823-25 the Aire And Calder Navigation company acquired the mill and redeveloped the site. Two new large waterwheels were built, and the site comprised the mill building, the manager's house, stables, workshop, warehouse and workers' cottages. The cottages were demolished in 1968, but the other buildings remain intact today.