Grenville is a village in Union County, New Mexico, United States. The population was 25 at the 2000 census. The village lost population for much of the twentieth century, but recent economic success bodes well.Grenville is located at 36°35′36″N 103°36′52″W / 36.59333°N 103.61444°W / 36.59333; -103.61444.According to the United States Census Bureau, the village has a total area of 0.6 square miles, all of it land.As of the census of 2000, there were 25 people, 9 households, and 6 families residing in the village. The population density was 39.8 people per square mile. There were 14 housing units at an average density of 22.3 per square mile. The racial makeup of the village was 100.00% White.There were 9 households out of which 33.3% had children under the age of 18 living with them, 66.7% were married couples living together, and 33.3% were non-families. 33.3% of all households were made up of individuals and 33.3% had someone living alone who was 65 years of age or older.