Rush Township is a civil township of Shiawassee County in the U.S. state of Michigan. The population was 1,409 at the 2000 census.
According to the United States Census Bureau, the township has a total area of 35.2 square miles (91.2 km²), of which, 35.2 square miles (91.2 km²) of it is land and 0.03% is water.
As of the census of 2000, there were 1,409 people, 505 households, and 413 families residing in the township. The population density was 40.0 per square mile (15.5/km²). There were 541 housing units at an average density of 15.4 per square mile (5.9/km²). The racial makeup of the township was 98.58% White, 0.07% African American, 0.35% Native American, 0.28% from other races, and 0.71% from two or more races. Hispanic or Latino of any race were 1.21% of the population.