Abstract: ER5183 welding wire was used to weld 8 mm thick 7A04 aluminum alloy plates by pulse TIG welding to study the effect of current waveform on the welding quality. The influence of welding current form in rectangular wave,sinusoidal wave and triangular wave on the microstructure and strength of the joint was studied. The results show that the stirring effect of molten pool and heat input are different due to the periodic change of different current waveforms, therefore the grain refinement degree and the microstructure of molten pool are affected. The weld microstructure with fine grain can be obtained by using pulse triangular waveform current welding, and the yield strength of the joint is better than that of the joint obtained by the other two current waveforms, and the yield to strength ratio of the joint is up to 0.95.