Deep River Township was organized February 28, 1873, at the time part of Bay County.

John Bullock, George H. Childs and Thomas White were appointed to oversee the first township meeting on the 1st Monday in April of that year [4] In 1886, Adams Township was split off from Deep River Township [5] According to the United States Census Bureau, the township has a total area of 35.5 square miles (92.0 km2), of which 35.3 square miles (91.4 km2) is land and 0.23 square miles (0.6 km2), or 0.70%, is water.

[6] As of the census[1] of 2000, there were 2,244 people, 839 households, and 614 families residing in the township.

There were 1,051 housing units at an average density of 29.7 per square mile (11.5/km2).

23.0% of all households were made up of individuals, and 10.6% had someone living alone who was 65 years of age or older.