Abstract: The solidification process of droplets is an important part of direct laser deposition (DLD).The final shape of the droplet on the manufacturing surface will directly affect the forming quality of the manufacturing layer.In order to clarify the solidification phenomenon and forming mechanisms of metal droplet in the direct laser deposition manufacturing process, a two-phase flow and heat transfer numerical model of metal droplets solidification on the cool wall was established.Based on the validation of the model correctness , the solidification of the droplets under strong and weak radiation were studied. The results show that under the action of weak surface radiation, the droplet spreads and contracts in an oscillatory manner on the cool wall, the maximum spreading speed of the front edge of the droplet can reach 25 mm/s, and the solidification of the droplet shows the solidification trend from the cool wall to the center and from the edge to the center. Under the action of strong surface radiation, the droplet solidifies from the outside to the inside, and there is no obvious spreading and shrinking movement. Compared with that of the weak radiation, the solidification rate of the droplet increases greatly, but with the deepening of solidification to the inside, the solidification rate presents a linear increasing trend.