Abstract: The characterizations of porosity in dual-beam laser welding with filler wire of LF6 aluminum alloys were studied. Compared with the single beam laser welding with filler wire and the dual-beam laser self-fusible welding,the dual-beam laser welding with filler wire can restrain the porosity formation. Especially, the dual-beam laser welding with parallel arrangement has a better effect on inhibition of porosity. Furthermore,the effects of shielding gas component and laser energy on porosity formation ratio were analyzed. The results show that,when the helium is used as the shielding gas,the area of plasma decreases as well as the shielding effect of the plasma on laser deceases,and the welding process become more stable. At the same time,the laser power must be proper,and both too high and too low laser power make the porosity formation ratio enlarged.