Deerfield Township is a civil township of Lapeer County in the U.S. state of Michigan. The population was 5,764 at the 2020 Census. There are no municipalities within the township, but Barnes Lake-Millers Lake is a census-designated place for statistical purposes. M-24 crosses the township north–south, with the city of Lapeer about nine miles south …Deerfield Township is a civil township of Lapeer County in the U.S. state of Michigan. The population was 5,764 at the 2020 Census. There are no municipalities within the township, but Barnes Lake-Millers Lake is a census-designated place for statistical purposes. M-24 crosses the township north–south, with the city of Lapeer about nine miles south of the center of the township. M-90 branches east off M-24 in the north of the township, with the village of North Branch about five miles to the east.