The Sharpenstine Farmstead is a historic farmhouse located at 98 East Mill Road near Long Valley in Washington Township, Morris County, New Jersey. It was added to the National Register of Historic Places on May 1, 1992, for its significance in architecture. The 22.4-acre (9.1 ha) farm overlooks the valley formed by the South Branch Raritan River. The house is part of the Stone Houses and Outbuildings in Washington Township Multiple Property Submission (MPS).