Washington Township is one of twenty townships in Allen County, Indiana, United States.

As of the 2010 census, its population was 36,092.

[4] Washington Township covers an area of 31.74 square miles (82.21 km2); 0.062 square miles (0.16 km2), or 0.20 percent of this is water.

[4] The township is adjacent to these Indiana townships: The township contains three cemeteries: Bethel, Hatfield, and Saint Pauls.