The 2020 census found 8,274 people in the township.

Located in the northern part of the county, it borders the following townships: Two incorporated villages are located in Harrison Township: Ashville in the southeast, and South Bloomfield in the southwest.

It is one of nineteen Harrison Townships statewide.

[4] The township is governed by a three-member board of trustees, who are elected in November of odd-numbered years to a four-year term beginning on the following January 1.

There is also an elected township fiscal officer,[5] who serves a four-year term beginning on April 1 of the year after the election, which is held in November of the year before the presidential election.