The method of laser welding with pre-melted liquid filler by arc is proposed, and the influence of incident energy on the melting state of the filler wire and the weld appearance is studied. The process adaptability of the welding process is further analyzed. The results show that, when the welding current is relatively low, the filler wire can be stably melted and filled into the molten pool, and the increase of the welding current is beneficial to increasing the melting length of the front-end filler wire. The increase of the laser power has no effect on the melting amount of the filler wire. The method of laser welding with pre-melted liquid filler by arc can reduce the porosity of weld and significantly improve the adaptability to assembly clearance.