Green Rock Branch is a long 2nd order tributary to Cherrystone Creek in Pittsylvania County, Virginia, USA.
Green Rock Branch rises about 1 mile south-southeast of Weal and then flows generally east to join Cherrystone Creek in the southwestern part of Chatham.
Green Rock Branch drains of area, receives about per year of precipitation, has a wetness index of 364.75, and is about 52% forested.