Dry Grove Township is located in McLean County, Illinois. As of the 2010 census, its population was 1,572 and it contained 618 housing units. It contains part of the census-designated place of Twin Grove.
Dry Grove Township took its name after Dry Grove, an area of forest at a relatively high and dry elevation.
According to the 2010 census, the township has a total area of , of which (or 99.92%) is land and (or 0.08%) is water.