The River Sheaf is a river in South Yorkshire, England. Its source is the union of the Totley Brook and the Old Hay Brook in Totley, now a suburb of Sheffield. It flows northwards, past Dore, through Abbeydale and north of Heeley, and then through the centre of Sheffield, where it is culverted. It re-emerges above ground at Lady's Bridge where it joins the River Don. Historically, the Sheaf—along with its tributaries the Meers Brook and the Limb Brook—formed part of the border between between the Anglo-Saxon kingdoms of Mercia and Northumbria, it remained on the border between Yorkshire and Derbyshire into the Twentieth Century.

The city of Sheffield derives its name from the Sheaf.

The main tributaries of the Sheaf are the Porter Brook and the Meersbrook.

The river has been polluted upstream through centuries of industrial activity, including iron and steel working, and is only slowly recovering. Along the river can be seen the Grade 1 listed Abbeydale Industrial Hamlet and Beauchief Abbey.