Abstract: The stress concentration generated by the pores in aluminum alloy by wire and arc additive manufacturing leads to the initiation and propagation of initial cracks, resulting in the deterioration of mechanical properties. The porosity formation cause of aluminum alloy parts by wire and arc additive manufacturing is introduced. The effects of shielding gas, welding speed, wire feeding speed, metal wire material, heat input, rolling and heat treatment on porosity are described. The future research direction of reducing porosity in aluminum alloy parts by wire and arc additive manufacturing is prospected.