Wisconsin Highway 45

State Trunk Highway 45 (often called Highway 45, STH-45 or WIS 45) was a number assigned to two different state highways in the U.S. state of Wisconsin:
 * Highway 45 from 1917 to 1923, along the current route of U.S. Highway 63 from Red Wing, Minnesota to Ellsworth, WIS 65 and WIS 35 up to Hudson
 * Highway 45 from 1923 to 1934, currently routed as Highway 34
 * For the highway in Wisconsin numbered 45 since 1934, see U.S. Highway 45.