Columbus Township is a civil township in St. Clair County in the U.S. state of Michigan. As of the 2000 census, the township had a total population of 4,615.
According to the United States Census Bureau, the township has a total area of 96.5 km2 (37.2 mi2). 96.1 km2 (37.1 mi2) of it is land and 0.4 km2 (0.1 mi2) of it is water. The total area is 0.38% water.