Utah State Route 166 may refer to:
- Utah State Route 166 (1969-1990), a former state highway in the Ogden Valley in eastern Weber County, Utah, United States that connected from Utah State Route 39 in Huntsville to Eden
- Utah State Route 166 (1933-1969), a former state highway in Daggett County, Utah, United States, that connected the Ashley National Forest with Utah State Route 43 "west of Antelope Canal"
See also