Walnut Township is one of seventeen townships in Adair County, Iowa, USA.

At the 2010 census, its population was 176.

[3] Walnut Township covers an area of 35.65 square miles (92.3 km2) and contains no incorporated settlements.

According to the USGS, it contains four cemeteries: Abandoned Timber, Canby, Oakwood and Saint Josephs.

This article about the geography of Adair County, Iowa is a stub.