The 26th Senate District of Wisconsin is one of 33 districts in the Wisconsin Senate. Located in south-central Wisconsin, the district comprises Downtown Madison, Wisconsin as well as most of the city's near west, south, east and north sides. The 26th also includes the suburban cities of Monona, the villages of Maple Bluff and Shorewood Hills, and most of the village of McFarland, in central Dane County. The district contains landmarks such as the Wisconsin State Capitol, the University of Wisconsin–Madison campus, the University of Wisconsin Arboretum, historic Forest Hill Cemetery, Edgewood College, Monona Terrace, Camp Randall Stadium, and the Kohl Center.

The Wisconsin Senate is the upper house of the Wisconsin State Legislature. Together with the larger Wisconsin State Assembly they constitute the legislative branch of the state of Wisconsin. The powers of the Wisconsin Senate are modeled after those of the U.S. Senate.