[4] According to the United States Census Bureau, the township has a total area of 34.9 square miles (90.4 km2), all land.

As of the census[2] of 2000, there were 324 people, 116 households, and 101 families residing in the township.

12.1% of all households were made up of individuals, and 2.6% had someone living alone who was 65 years of age or older.

Osborne Township is located in Minnesota's 1st congressional district, represented by Mankato educator Tim Walz, a Democrat.

At the state level, Osborne Township is located in Senate District 22, represented by Republican Doug Magnus, and in House District 22A, represented by Republican Joe Schomacker.