Through the observation and analysis on the surface formation and the milling test of hard alloy under power-density conditions of high and low pulse lasers, it shows that there exist three modes of material removal mechanism milled by pulse laser, including immediate gasification, ejection after being melted, and ablation of material surface. In the process of pulse laser milling, these three modes coexist but plays a different role under different conditions. In the test, under the condition of a low power-density, the removal mechanism for hard alloy material is primarily ejection; under a high power-density condition, the milling surface of the hard alloy shows some fracture in formation, that is, the ablation as the main mode. In the last part, some applications of pulse laser milling are briefly introduced.