Abstract: The effect of the parameters on weld appearance quality during laser welding with filler wire is studied in the article.The appearance quality obtained by controlling the wire feeding speed is compared with that obtained by controlling welding speed during laser welding with variable gap-width.The result shows that it is better to control wire feeding speed for narrower gap-width,otherwise it is better to control welding speed for wider gap-width.To meet the weld appearance quality requirement during high accuracy welding process,the double MCU system based on 80c51 is developed,which can adjust the welding parameters by gap-width during welding process to assure benign weld appearance quality during laser welding with filler wire.