Green Valley is a village in Tazewell County, Illinois, United States. According to the 2010 census, Green Valley has a total area of 0.3 square miles, all land. As of the census of 2000, there were 728 people, 262 households, and 205 families residing in the village. The population density was 2,360.6 inhabitants per square mile. There were 280 hou…Green Valley is a village in Tazewell County, Illinois, United States. According to the 2010 census, Green Valley has a total area of 0.3 square miles, all land. As of the census of 2000, there were 728 people, 262 households, and 205 families residing in the village. The population density was 2,360.6 inhabitants per square mile. There were 280 housing units at an average density of 907.9 per square mile. The racial makeup of the village was 99.04% White, 0.14% African American, 0.27% Native American, 0.27% Asian, and 0.27% from two or more races. Hispanic or Latino of any race were 0.69% of the population.