Minnesota State Highway 43 (MN 43) is a highway in southeast Minnesota, which runs from its intersection with State Highway 44 in Mabel and continues north to its northern terminus at the Wisconsin state line at Winona, where it becomes Wisconsin Highway 54 upon crossing the Mississippi River.

Highway 43 is 45 miles (72 km) in length.

State Highway 43 serves as a north–south route between Mabel, Rushford, and Winona in southeast Minnesota.

The route crosses the Root River in Fillmore County.

Highway 43 passes through the Richard J. Dorer State Forest.

The northern terminus of Highway 43 is at the Mississippi River at Winona, where the route becomes Wisconsin Highway 54 upon crossing the Main Channel and North Channel bridges over the river to Wisconsin.

State Highway 43 was authorized in 1920 between Rushford and Winona. The remainder of the route between Rushford and Mabel was authorized in 1933.

Highway 43 was paved from Wilson to Winona by 1929. The only gravel section remaining by 1940 was south of Rushford. The route was completely paved by 1953.

A major project in the 1980s to rebuild Highway 43 from Interstate 90 to Winona as an expressway ran out of money. Only one carriageway was actually paved. There is still visible road bed and bridges east of the roadway in this section.

In response to the I-35W Bridge collapse in Minneapolis on August 1, 2007, all Minnesota bridges were ordered to be inspected. During an inspection, "gusset plate corrosion issues" were discovered in the Main Channel Bridge (Highway 43 / Highway 54), which crosses the Mississippi River between Winona, MN and nearby Fountain City, WI. The Main Channel Bridge (Bridge #5900) was closed to traffic on June 3, 2008. MnDOT made a statement this was due to gusset plate corrosion issues similar to those that caused the I-35W Bridge to collapse. The Main Channel Bridge reopened to car traffic on June 14, 2008. Commercial vehicles were still directed to find alternate routes across the river. The bridge was scheduled for replacement in 2017, which has been moved up to 2014.

County	Location	mi	km	Destinations	Notes
Fillmore	Newburg Township	0.000	0.000	MN 44 – Caledonia, US 52	Southern Terminus
	Rushford Village	21.677	34.886	MN 16 east (Historic Bluff Country Scenic Byway) – Houston	South end of MN 16 overlap
	Rushford	22.211	35.745	MN 16 west (Historic Bluff Country Scenic Byway) – Preston, Root River State Trail	North end of MN 16 overlap
		22.401	36.051	MN 30 west
Winona	Warren Township	32.381	52.112	I-90 west – Austin	West end of I-90 overlap
	Wilson Township	35.186	56.626	I-90 east – La Crosse	East end of I-90 overlap
	Winona	42.100	67.753	US 14 / US 61 / Great River Road	formal traffic/stop light; made into a roundabout in 2022.
Mississippi River		45.334	72.958	Main Channel Bridge and North Channel Bridge; Minnesota–Wisconsin state line
Buffalo	Town of Buffalo			WIS 54 east – Galesville	Continuation into Wisconsin
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus