Deerfield is a city in Dane County, Wisconsin. The population was 2,319 at the time of the 2010 census. The city is located within the Town of Deerfield. It is part of the Madison Metropolitan Statistical Area. Towns and villages near Deerfield include Marshall, Medina, London, Cambridge, and Cottage Grove, Wisconsin.

Dane County is a county in the U.S. state of Wisconsin. As of the 2020 census, the population was 561,504, making it the second-most populous county in Wisconsin after Milwaukee County. The county seat is Madison, which is also the state capital.