Abstract: In order to research the effect of nozzle in aluminum welding, several different structure nozzles were designed, and theoretical analysis and experimental verification were performed. The effect of gas outflow from different structural nozzles was analyzed. The working angle that can be achieved by the different nozzles were calculated under the same process conditions. And the effects of various nozzles on aluminum welding performance under different methods were analyzed through welding experiment. The study of nozzles on aluminum welding in this paper have a certain guiding significance and reference value in the welding field.