Janesville is a city in Waseca County, Minnesota, United States. The population was 2,256 at the 2010 census.
U.S. Route 14 serves as a main arterial route in the community, running East-West south of Janesville. County Road 3 runs North-South through the town. There is one disabled stoplight, now a four way stop, in Janesville at the intersection of Country Road 3 (Main Street) and the old Highway 14.
According to the United States Census Bureau, the city has a total area of 1.3 square miles (3.3 km²), all of it land.