Sentinel Butte is a city in Golden Valley County, North Dakota, United States. The population was 61 at the 2020 census. Sentinel Butte was founded in 1902 along the transcontinental rail line of the Northern Pacific Railway. The name comes from the prominent butte three miles to the south. This geographical feature was named in honor of two Arikara sentinels killed nearby in 1864 by the Sioux.