[1] The highway runs in roughly a "U" shape along section line roads, dipping southward from Vinton then east parallel to I-10 and back to the north toward Sulphur.

LA 108 enters into an interchange with I-10 and continues north for 1.4 miles (2.3 km) through the Maplewood area of Sulphur to a terminus at US 90 (East Napoleon Street).

It then widens to a divided, four-lane highway from there to I-10 in Sulphur, after which the median is replaced by a center turn lane for the remainder of its route to US 90.

[4][5][6] LA 108 was created with the 1955 Louisiana Highway renumbering,[7] and its route has remained unchanged to the present day except for a small truncation on the western end.

LA 108 proceeded east on Center Street then turned south onto Gum Cove Road where it met the present western terminus at what is now the I-10 interchange.