The River Brock is a river running through the county of Lancashire in England.
Commencing its journey on Fair Snape Fell, the infant River Brock runs beneath the Bleasdale Circle before continuing via Claughton and Bilsborrow to St Michael's On Wyre, where it joins the River Wyre. A significant length of River Brock forms the northern bounrdary of City of Preston, Lancashire.
Coordinates: 53°51′N 2°49′W / 53.850°N 2.817°W