Abstract: This paper investigates the fatigue performance of aluminum alloy 3D printing materials. It first outlines the basic principles of aluminum alloy fatigue performance, including fatigue failure mechanisms and influencing factors such as defects and stress. Next, it analyzes the impact of 3D printing technology on aluminum alloys, focusing on microstructural changes and performance alterations. The discussion delves into how internal defects and process parameters affect the fatigue performance of aluminum alloy 3D printing materials, including common defect types and distributions, as well as the relationship between fatigue performance and the laser power, scanning speed, layer thickness and other process parameters. Strategies for enhancing fatigue performance are proposed, including material composition optimization and process improvements. Finally, the research is summarized and the future research direction is prospected, which provides theoretical basis and practical guidance for improving the fatigue properties of aluminum alloy 3D printing materials.