Abstract: The metal transfer and the conrresponding arc voltage and welding current in twin-wire indirect arc argon welding was investigated with high speed camera system based on a xenon lamp source and digital oscillogragh.Results showed that with the different matching of welding current and arc voltage,the mode of metal transfer consists of short circuiting transfer,globular transfer,mixing transfer,projected transfer and streaming transfer etc.With the increasing of welding current,the droplet size reduces,and the droplet is refined.With the raising of arc voltage,the size of droplet reduces.There is well corresponding relationship between metal transfer mode and the oscillogram of volgtage and welding.