Abstract: The paper focused on the research progress on detection and quality control for metal additive manufacturing. In terms of typical detectable features in metal additive manufacturing, the characteristics of the melt pool state and the types and formation mechanisms of defects such as pores, cracks, and lack of fusion were introduced. Regarding metal additive manufacturing detection technology, the post detection technology utilizing ultrasound and CT, as well as online detection technology using infrared, visible light, X-ray, and acoustics, and the latest achievements of online detection combined with multiple sensors were introduced. In terms of closed-loop quality control, the research progress of combining closed-loop feedback control methods such as PID control and fuzzy control to realize quality control was introduced. Finally, the future research direction of metal additive manufacturing detection technology was pointed out.