To stabilize an automated guided vehicle in an intersection when it travels over diagonally crossing travel guide lines from either side.

In the intersection between the both travel guide lines 11 and 11a, an auxiliary guide part 15 with a radius r is arranged around the intersection P on the floor. The radius r of the magnetic tape type auxiliary guide part 15 is longer than the length of the crossing part between the end of a detection area S for the automated guided vehicle 1 and the travel guide line 11a on which another automated guided vehicle 1a travels. When the automated guided vehicle 1 travels along the travel guide line 11, a magnetic guide sensor main body 2 detects the auxiliary guide part 15. The auxiliary guide part 15 is positioned evenly on both sides of the travel guide line 11, so that it is determined that the center part of the sensor turned on inside the magnetic guide sensor main body 2 is the center of the automated guided vehicle 1.