To provide a substrate inspection device capable of inspecting a prescribed marking on an objective substrate between each manufacturing process in a short time with a simple structure.

This substrate inspection device is provided with a roller conveyer 1 conveying an objective substrate 4 provided with prescribed markings formed on at least four corners, a gantry arm 10 straddling over the conveyer, two inspection heads 13 and 14 which are provided so as to move along a horizontal beam of the gantry arm in a direction orthogonally intersecting a moving direction of the objective substrate and arranged in the same direction as the moving direction of the objective substrate at prescribed intervals, image pickup means 19 and 20 for picking up images of the markings on the objective substrates provided on the two inspection heads respectively, and a control means 5 controlling the two inspection heads for the movement by a predetermined distance simultaneously and displaying an observed image of the each marking after picking up the images of the markings at positions set respectively with the two image pickup means.