State Trunk Highway 181 (often called Highway 181, STH-181 or WIS 181) is a 21.44-mile (34.50 km) state highway in Milwaukee and Ozaukee counties in Wisconsin, United States, that runs north–south in southeast Wisconsin from West Allis to Cedarburg.

This section needs expansion. You can help by adding to it. (May 2015)

WIS 181 begins at WIS 59 in West Allis near the Wisconsin State Fairgrounds as 84th Street. After passing by the fairgrounds, 84th Street crosses under I-94 and becomes Glenview Avenue. Prior to entering Wauwatosa, the route intersects U.S. 18 and exits the downtown area as 76th Street. WIS 190 and WIS 175 are intersected prior to WIS 181 crossing over WIS 145 and Silver Springs Drive. Before leaving Ozaukee County, WIS 181 crosses over WIS 100 and enters Ozaukee County in Mequon. The only major intersection prior to ending at WIS 60 near Cedarburg is at the intersection of WIS 167 in Mequon.

County	Location	mi	km	Destinations	Notes
Milwaukee	West Allis			WIS 59 (W. Greenfield Avenue)
	Milwaukee			I-94
	Wauwatosa			US 18 (Bluemound Road)
	Milwaukee			WIS 190 (W. Capitol Drive)
				WIS 175 (W. Appleton Avenue)
				WIS 145	Interchange
				CTH-E (W. Silver Springs Drive)	Interchange
				WIS 100 (W. Brown Deer Road) – Brown Deer, Menomonee Falls	Interchange
Ozaukee	Mequon			WIS 167 (Mequon Road)
	Town of Cedarburg			WIS 60 / CTH-NN north – Jackson (village), Grafton, West Bend
1.000 mi = 1.609 km; 1.000 km = 0.621 mi

• U.S. Roads portal

• Media related to Wisconsin Highway 181 at Wikimedia Commons