Erin Township is one of sixteen townships in Hancock County, Iowa, USA. As of the 2000 census its population was 218.
Erin Township was organized in 1879. It was originally settled chiefly by Irish immigrants, who named it Erin, the poetic form of Ireland.
According to the United States Census Bureau, Erin Township covers an area of 36.37 square miles (94.19 square kilometers).
The township contains Saint Patrick's Cemetery.