Abstract: Using ultra high-power laser-arc hybrid welding at myriawatt level is an important research direction in the field of laser processing. Characteristic of laser-MAG hybrid welding, laser-TIG hybrid welding with filler wire and laser-MAG hybrid welding with filler wire were systematically analyzed by studying the plum and spatter which were produced in the welding process and investigated by a high speed camera when laser power increases from 5kW to 30 kW. The results showed that both the mean value of plum and spatter area and their fluctuation increased with the laser power increase. The addition of cold wire reduces the weld penetration and makes the stability of laser-MAG hybrid welding process become worse. The stability of the laser-TIG hybrid welding process with filler wire is better than the other two welding method. The scattering and absorbing of laser by the high temperature plume is the essential reason for the weld penetration increase slowly and weld width increase fastly in high power laser-arc hybrid welding.