State Route 133 is a highway completely within Millard County in central Utah that connects Interstate 15 to Kanosh while passing through Meadow. The route serves as both communities' Main Street in its seven mile (11 km) span.

From the southern terminus at the southern city limits of Kanosh, the route runs north as a two-lane undivided highway through the town before turning northeast. It continues this direction until reaching Meadow, where it turns north again. It maintains this direction until its northern terminus with I-15.

When this designation was formed in 1933, the route ran from SR-2, now Interstate 80, in Coalville to the Wyoming border via Pine View. This route was deleted in 1969.

The current route of SR-133 was formed in the same year the old route was deleted, 1969. When it was first formed, it made a partial loop around SR-1 (Interstate 15). In 1975 the portion of the highway from the southern terminus of I-15 to the southern Kanosh city limits was deleted, forming the current route.

The entire route is in Millard County.