AUTOMATIC TRAVEL CONTROLLING DEVICE

An automatic travel controlling device capable of reliably guiding a vehicle along a lane even if the white lane lines cannot be detected. A laser radar device for detecting the distance to a side wall of the lane is provided to the left and right in addition to a CCD camera for detecting the white lane lines. An image from the CCD camera is supplied to a image processor ECU, and an extracted white line is supplied to a vehicle controlling ECU. A vehicle controlling ECU drives a steering actuator to perform steering control based on two white lines of the lane when detected. However, when the white lines cannot be detected, steering control based on the distances to the side walls is performed. If an obstacle is detected ahead by the laser radar device, the vehicle position is detected based on the distances to the side walls and a lane change is performed to evade the obstacle.