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.

The 2020 Wisconsin Senate elections were held on Tuesday, November 3, 2020, at the Fall general election in Wisconsin. Sixteen of the 33 seats in the Wisconsin Senate were up for election—the even-numbered districts. Before the election, Republicans held 18 seats, Democrats held 13 seats, and 2 seats were vacant. Of the seats up for election, 7 were held by Republicans, 7 were held by Democrats, 1 was vacated by a Democratic resignation, and 1 was vacated by a Republican resignation. The primary election was held on August 11, 2020.