State Route 168 has existed as part of Nevada's state highway system since 1919. In that year, the
Nevada Legislature amended the general highway law to add State Route 7, which was vaguely defined as "commencing at the city of
Ely and running thence southerly through
Pioche to
Las Vegas." The southern terminus of SR 7 was later truncated to Glendale, with its southernmost miles following the alignment of present-day SR 168. At a meeting held on June 8, 1931, the
American Association of State Highway Officials (AASHO) approved an extension of
U.S. Route 93 through Nevada. This extension brought the southern end of that route from
Wells to Glendale. South of Ely, the extension of US 93 was routed over State Route 7, including the portion northwest of Glendale. The routing of US 93 via the Glendale–Moapa segment remained in place until 1967. In that year, a shorter route connecting Las Vegas and
Caliente was completed, bypassing Glendale. The of highway northwest of Glendale remained in the state highway system, still marked as State Route 7. After the removal of US 93 from the route, the southerly segment of SR 7 remained unchanged for several years. On July 1, 1976, the Nevada Department of Transportation initiated the
renumbering of Nevada's state highways. In this process, the highway was renumbered to State Route 168. This change was first seen on the 1978 edition of the state's highway map. ==Major intersections==