[4] According to the United States Census Bureau, the township has a total area of 54.2 square miles (140 km2), of which 0.02% is water.

The Little Fork River flows through the southern portion of Field Township.

Flint Creek flows through the central portion of Field Township.

The North Branch of Flint Creek flows through the northeast part of the township.

The northern 1/3 portion of Field Township is located within the Kabetogama State Forest.

The racial makeup of the township was 96.68% White, 2.05% Native American, 1.28% from other races.