Route 334 is a Connecticut state highway in the Naugatuck River valley, running from Seymour to Ansonia.

Route 334 begins at an intersection with Route 188 near the Seymour-Oxford town line and heads southeast. As it approaches the Seymour-Derby town line, it turns northeast past the Fountain Lake Reservoir and briefly along the Seymour-Ansonia turn line before crossing into Ansonia. In Ansonia, it intersects Route 8 and turns south and southeast, crossing the Naugatuck River before ending at an intersection with Route 115 near the Ansonia railroad station.

As part of the 1962 Route Reclassification Act, Great Hill Road in Ansonia and Seymour was taken over by the state and designated as SR 734. With the opening of the Route 8 expressway, the old surface alignment of Route 8 in Derby and Seymour was designated as SR 735 in 1960. In the 1962 Route Reclassification, most of this had been turned over to the towns. SR 735 was reconfigured to instead follow Franklin Street towards downtown Ansonia instead. Route 334 was commissioned 1963 from SR 734 and the reconfigured SR 735 and has had no significant changes since.

The entire route is in New Haven County.

Location	mi	km	Destinations	Notes
Seymour	0.00	0.00	Route 188 – Derby, Oxford, Southford	Western terminus of Route 334
Ansonia	3.07	4.94	Route 8 – Bridgeport, Waterbury	Exit 15 on Route 8
	4.40	7.08	Route 115 – Seymour, Derby	Eastern terminus of Route 334
1.000 mi = 1.609 km; 1.000 km = 0.621 mi