Mary E. Panzer (September 19, 1951) is a Wisconsin banker and Republican politician, daughter of former state senator Frank E. Panzer.
Born in Waupun, Wisconsin, Panzer was educated at the University of Wisconsin–Madison, after which she was a banker and worked in the Wisconsin State Legislature.
In 1980, Panzer was elected to the Wisconsin State Assembly in a special election to replace fellow Republican James R. Lewis (who had been convicted of perjury). (She had almost defeated then-incumbent Lewis in the 1974 Republican primary.) She served until 1993, when she was elected to the Wisconsin State Senate in another special election. Panzer eventually rose to be the majority leader of the senate.
In the Republican primary election in September 2004, Panzer was herself defeated for renomination by State Assemblyman Glenn Grothman, who alleged that she was not sufficiently conservative for the modern-day Republican Party. Grothman won with a vote of 79% to 21% for Panzer.