Robert de Stafford (known also as Robert of Tosny and Robert de Toeni) (c. 1039 – c. 1100) was a Norman nobleman, the builder of Stafford Castle in England. He is generally said to have been a son of Roger I of Tosny; primary evidence is lacking to determine his parentage, according to Cawley. Cawley notes that Robert de Stafford is connected to the Tosny family through a charter (not dated) under which "Robertus de Stafford" confirmed donations to Wotton Wawen Abbey, Warwickshire by "avus meus Robertus de Toenio et pater meus Nicolaus de Stafford." Also "Robertus de Staffordia et Robertus filius meus et hæres" confirmed donations of property to Evesham Monastery by "Rodbertus avus meus...et pater meus Nicholaus" by undated charter.
He held a large number of lordships in the Domesday Survey, a high proportion lying in Staffordshire. They included Barlaston and Bradley in Staffordshire and part of Duns Tew in Oxfordshire.
Robert de Stafford was buried in Evesham Abbey.
Although some sources say that he married Adelisa de Savona, with whom he had a daughter Adelisa de Toeni, who married Roger Bigod, 1st Earl of Norfolk, the Adelisa de Tosny who married Roger Bigod was in fact the heiress of Belvoir and was clearly the daughter of Robert de Tosny Lord of Belvoir and his wife Adeliza fitzOsulf du Plessis, through whom Belvoir had been inherited, since the honour of Belvoir was then passed to Cecily Bigod, the daughter of Roger and Adelisa Bigod.
Robert de Stafford apparently married Avice de Clare, with whom he had sons, variously listed as.
The Gresley family of Drakelow, baronets, were descendants of the de Tosny family through their de Stafford ancestors, including Robert.