To precisely measure the speed of a running automobile based on the image from an image pickup camera mounted on the upper part of support pole stood at a side of the roadway.

An image of a running automobile 2 is picked up by an image pickup camera 3 provided at a side of a roadway 1, then a vertical traveling amount of the traveling image of the automobile 2 displayed on a screen is calculated, and also the horizontal traveling amount of the traveling image on the screen is calculated. Thereafter, both the calculated vertical and horizontal traveling amounts are converted to the vertical and horizontal traveling amounts in an actual space based on both image pickup position information and posture information of the image pickup camera 3 in the actual space. Then, the speed of the running automobile 2 is calculated from the vertical and horizontal traveling amounts in the actual space and the traveling time.