Abstract: Based on the principle of stereoparallax range finding, two images of a scene are taken by the left and the right pickup cameras at the same time. According to the stereoparallaxes of corresponding points in the two images, distance data of three dimensions between target point and the pickup camera can be calculated and a map of the sight for making path plan can be obtained. This paper provides an approach for machine vision of automatic guided vehicle. This method which is verified in laboratory is practicable and suitable for agricultural development.