As for the difficulty of measuring the dispersion of three projectiles impacting simultaneously，a method for measuring coordinate by using a single color linear array CCD camera was presented. A highspeed color linear array CCD camera was used, with red, blue and green sectorlike line laser modules as the light source. When passing through the sharing screen of the CCD camera and the light source, the projectiles left projections on the projection board. Meanwhile, the camera captured the images of the projections and projectiles. Then the projection coordinates was identified and calculated by image processing and coordinate computation. By the principle of linear intersection, the impacting coordinates was obtained. The measuring principle and derivation of the measurement formula were described, and the measurement errors were analyzed and simulated. The proposed method, which proves to be effective in measuring the dispersion of three projectiles impacting simultaneously, provides guidance for the development of measuring system for the impacting coordinate of high RF weapons and multibarrel weapons.