Automatic travelling system of construction vehicle

An automatic travelling system of a construction vehicle for the purpose of remarkably decreasing the number of guide lines laid to reduce the installation cost and making the guiding operation of a vehicle accurate and easy. The automatic travelling system of a construction vehicle comprises a plurality of guide lines (L, 9 or l) serving as a main traveling path means for a vehicle (V or 22) and disposed on a traveling road surface for the vehicle disposed between a raw material site (1) and raw material depots (6a-6e) of a plant (5); and a plurality of detectors (D, 23 or 34) provided on the vehicle so as to detect the guide lines. Each of the guide lines is a guide cable or a laser beam.