An industrial machine comprises an industrial machine main unit, a construction working implement installed on the industrial machine main unit, two cameras each mounted at a known position with respect to a machine center of the industrial machine main unit, at least three targets being installed on the working implement so that the targets are within visual field of each of the two cameras, and an arithmetic processing device. The arithmetic processing device is used for extracting the images of at least three targets in common to the images from stereo-images taken by the two cameras, for obtaining a three-dimensional position of each target image, and for calculating a position and a posture of the working implement with respect to the industrial machine main unit based on the three-dimensional position obtained.