Janesville is a city in Waseca County, Minnesota, United States. The population was 2,109 at the 2000 census. U.S. Route 14 serves as a main arterial route in the community, running horizontally south of Janesville. County Road 3 runs vertically through the town. There is one stoplight in Janeville at the intersection of Country Road 3 (Main Street) and the old Highway 14.