Green Valley is a village in Tazewell County, Illinois, United States. It is south of Pekin near the county border along Illinois State Route 29. The population was 728 at the 2000 census. There is an assisted living facility, Mardell Manor, in the village.Green Valley is located at 40°24′31″N 89°38′39″W / 40.40861°N 89.64417°W / 40.40861; -89.64417.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 people 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.There were 262 households out of which 41.2% had children under the age of 18 living with them, 66.