Sour John is a census-designated place (CDP) in Muskogee County, Oklahoma, United States. The population was 71 at the 2020 census. and to the east by Sequoyah and Cherokee counties. State Highway 10 leads north to Fort Gibson and southeast to Gore.
According to the U.S. Census Bureau, the Sour John CDP has a total area of , all land.
There were 27 households in Sour John, of which 14.8% had children under the age of 18 living in them. Of all households, 81.5% were married-couple households, 7.4% were households with a male householder and no spouse or partner present, and 3.7% were households with a female householder and no spouse or partner present. About 3.7% of all households were made up of individuals and 3.7% had someone living alone who was 65 years of age or older.
! Race !! Number !! Percent
|-
| White || 45 || 63.4%
|-
| Black or African American || 0 || 0.0%
|-
| American Indian and Alaska Native || 13 || 18.3%
|-
| Asian || 0 || 0.0%
|-
| Native Hawaiian and Other Pacific Islander || 0 || 0.0%
|-
| Some other race || 0 || 0.0%
|-
| Two or more races || 13 || 18.3%
|-
| Hispanic or Latino (of any race) || 0 || 0.0%
|}
2010 census
As of the 2010 census, the population of Sour John was 60.