Banner Township is a township in Ashley County, Arkansas, United States. Its total population was 158 as of the 2010 United States census, a decrease of 7.6 percent from 171 at the 2000 census.
According to the 2010 Census, Banner Township is located at (33.281880, -91.607009). It has a total area of , of which is land and is water (1.74%). As per the USGS National Elevation Dataset, the elevation is .