The Grenfell railway line is a partly closed railway line in New South Wales, Australia. It branches from the Blayney- Demondrille line at the town of Koorawatha. The line opened in 1901, and closed between Greenethorpe and Grenfellin 1991.
From the opening, until the demise of steam, there were two locations where locomotives could obtain water, Koorawatha and Grenfell. The stand at Grenfell was supplied from a purpose-built dam some 1.6 km away.
Grain services operate between Koorawatha and Greenethorpe. Passenger services operated until 1974. The line is owned by the NSW government, but in 2004 the Australian Rail Track Corporation became responsible for co-ordinating operations over the line.