The Forty-Fifth Wisconsin Legislature convened from January 9, 1901, to May 15, 1901, in regular session.

[1] Senators representing even-numbered districts were newly elected for this session and were serving the first two years of a four-year term.

Assembly members were elected to a two-year term.

Senators representing odd-numbered districts were serving the third and fourth year of a four-year term, having been elected in the general election of November 8, 1898.

[1] The governor of Wisconsin during this entire term was Republican Robert M. La Follette, of Dane County, serving a two-year term, having won election in the 1900 Wisconsin gubernatorial election.