Route 174 is a short highway in southwestern Missouri. Its eastern terminus is at U.S. Route 60/Route 413 in Republic, its western terminus is at Route 39 in Mount Vernon. It is a two-lane highway its entire length and was originally part of U.S. Route 166 between Republic and Mount Vernon. After the construction of Interstate 44 which replaced US 166 from Mount Vernon to Joplin, the highway was redesignated as Route 174.

Except for the endpoints, the only town on Route 174 is the unincorporated community of Chesapeake.

County	Location	mi	km	Destinations	Notes
Lawrence	Mount Vernon	0.000	0.000	Route 39 / Route 39 Bus. begins – Mount Vernon, Miller	Western end of Route 39 Business overlap
		0.567	0.912	Route 39 Bus. south (Main Street)	Eastern end of Route 39 Business overlap
	Mount Vernon Township	3.729– 3.751	6.001– 6.037	I-44 – Springfield, Joplin	exit 49
Greene	Republic	20.715– 20.740	33.338– 33.378	US 60 / Route 413 – Billings, Springfield
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus

Route 38, designated in 1922, part of which is now Route 174.