Johnstone Ridge () is a mainly ice-free ridge in the Britannia Range, extending 7 nautical miles (13 km) north from Mount Olympus toward the south side of Hatherton Glacier. Named by Advisory Committee on Antarctic Names (US-ACAN) for Graeme N. Johnstone, a member of the Byrd Substation auroral party, winter 1962, and the McMurdo Station winter party, 1964.
This article incorporates public domain material from the United States Geological Survey document "Johnstone Ridge" (content from the Geographic Names Information System).