Maltby is a town and civil parish in the Metropolitan Borough of Rotherham, South Yorkshire, England. It was historically in the West Riding of Yorkshire. It is located 6 miles (10 km) east of Rotherham and 10 miles (16 km) north-east of Sheffield. It forms a continuous urban area with Hellaby, separated from the rest of Rotherham by the M18 motorway. It had a population of 16,688 at the 2011 Census.

The place-name 'Maltby' is first attested in the Domesday Book of 1086, where it appears as Maltebi. The name means 'Malti's homestead or village'. Malti was a common Old Danish name.

Maltby was for centuries a small village near a stream based around farming. Roche Abbey, on the outskirts of Maltby, was founded in 1147 by Cistercian Monks from Newminster Abbey (near Morpeth, Northumberland), and was suppressed during the Dissolution of the Monasteries in the reign of Henry VIII.

Coal was discovered in the area in the late 19th century; the last colliery in Rotherham was Maltby Main Colliery, established 1910 and faced with closure in March 2013. To house the colliery's workers, the colliery company built a large estate known as the 'Model Village' to the east of the town centre.

From 1900 until 1929, the town was served by Maltby railway station on the South Yorkshire Joint Railway, with services running between Doncaster and Worksop. The station's platforms still remain and the line is an important freight route. John Brown's Private Railway also ran by the west of Maltby, but the track has been lifted and is now a public footpath; a short stretch of track and a platform remains. During the Second World War, a munitions factory, ROF Maltby, was established on the outskirts of Maltby close to the colliery; an estate nicknamed 'Little London' was built to house its workers, who had moved from Enfield in London.

Maltby also had a knitwear factory, Byfords, which supplied companies including Pringle – but this closed in 1999, and a police station was built on the site.

Maltby's main council housing stock went into serious disrepair during the 1980s with areas like "White City" and the "Tarran estate" (now demolished) worst affected. Maltby local government funding in 1997, council estates such as White City and Birk's Holt Drive have been redevelopment. Derelict land and a former club building was demolished and the land redeveloped during the 1990s by John & Jeanne Jebson and Richard & Jen Schofield who developed two private dwellings on Meadow Lane and developed individual building plots and named Foxcroft Meadows – an area of seven new builds. New council housing was opened in 2011 on the site of the former Tarran estate.

Maltby has historically been connected with the peerage title of Earl of Scarbrough. Sandbeck Park in Maltby has been the family seat of the Earl of Scarbrough since 1752. The title of Earl of Scarbrough is synonymous with the Lumley family, who have held the title since its creation. The present holder of the title is Richard Lumley.