High power diode laser vertical stack’s collimated beam pointing error and the influence of the pointing on the laser beam are introduced. The experimental device is built, and single anastigmatic far field lens are adopted to collect the light spot of the vertical stacking. By combining the centroid arithmetic measured continuous work 2 kW vertical stacking diode laser, the results of collimation beam's pointing accuracy was ±1.7 mrad. The errors of the metrical method are analyzed and some routes are optimized to improve the metrical method.