Oak Grove is a village in Rock Island County, Illinois, United States.

[2] According to the 2010 census, Oak Grove has a total area of 0.57 square miles (1.48 km2), all land.

[3] The population listed in the 2000 U.S. Census mistakenly included the population of the East Moline Correctional Center which is actually located in East Moline apparently mistaking Hillcrest Road in Oak Grove as the road of the same name where the prison is located in East Moline.

[5] The actual count for 2000 would be 220 comprising the listed 1,318 less the 1,098 increase to East Moline's population.

There were 114 housing units at an average density of 180.6 per square mile (69.7/km2).