Joan A. Ballweg (née Gottinger; born March 16, 1952) is an American business owner and Republican politician from Green Lake County, Wisconsin.

Ballweg entered the Republican primary in March 2004, citing her experience in education, local government, small business, and the health care industry.

[7] The race ultimately attracted a huge number of ambitious area Republicans, including the former Green Lake County sheriff, Lance Buchholtz, and Ballweg's successor as Markesan mayor, Rich Slate.

[1] During the Trump administration, she also served as a member of the Federal Emergency Management Agency Region V advisory council.

[11] She faced retired union machinist Joni Anderson in the general election, and prevailed with 65% of the vote.

[12] In the state Senate, Ballweg was again elected to leadership, serving as caucus vice chair in the 2023 term.

[1] In 2023, the Wisconsin Supreme Court struck down the Republican legislative gerrymander and compelled the Legislature to adopt remedial maps for the 2024 elections.