Stillwater River may refer to:
New Zealand Stillwater River (New Zealand), on the South Island
United States Stillwater River (Maine) Stillwater River (Nashua River tributary), Massachusetts Stillwater River (Stillwater County, Montana), a tributary of the Yellowstone River Stillwater River (Flathead County, Montana), a tributary of the Whitefish River Stillwater River (Ohio) Stillwater River (Rhode Island)
See also
Stillwater (disambiguation)