Based on the supply problem of the equipment spare parts in the poor timeliness and the low accuracy during the wartime, this paper studies applying the laser stereo forming technology in the weapon parts for the supply. The 316L stainless steel is selected as the printing material in the experiment. And based on the control variable method, it takes the three major parameters of the laser power, the scanning speed and the powder feeding rate as variables to study the influence on the rule and mechanism of the processing parameters on macro forming quality. The results show that the height decreases with the increase of the laser power and the scanning speed, and the height increases with the increase of the powder feeding rate. The width is basically unchanged, which is mainly affected by the size of the spot.