Sioux Township is a township in Clay County, Iowa, USA.

Sioux Township was created in 1894.

[1] Sioux Township covers an area of 30.45 square miles (78.9 km2) and contains no incorporated settlements.

The streams of Big Muddy Creek, Little Muddy Creek, Lost Island Outlet and Prairie Creek run through this township.

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