SH 342 was designated on November 24, 1941 over a former alignment of US 77 from the current alignment of US 77 in Red Oak to Spur 260 (Commerce Street) in Dallas, as US 77 was rerouted over SH 197.

On June 25, 1991, the northern terminus was changed to I-30 with the removal of the portion north of I-30 from the State Highway System and returned to the city of Dallas.

It heads north from this junction to two other intersections in Red Oak, FM 2377 (locally known as Louise Ritter Boulevard) and FM 664 (locally known as Ovilla Road).

Heading towards the north, the highway continues to an intersection with Interstate 20 in Dallas.

SH 342 reaches its northern terminus at Loop 12 in Dallas.