 Rolling Green Township was named for the rolling green hills within its borders.According to the United States Census Bureau, the township has a total area of 35.7 square miles (92.4 km²), of which 34.9 square miles (90.4 km²) of it is land and 0.8 square miles (1.9 km²) of it (2.10%) is water.As of the census of 2000, there were 309 people, 113 households, and 89 families residing in the township.