Abstract: Selective laser melting (SLM) has been widely adopted in high-precision manufacturing fields such as aerospace due to its advantages in rapid forming of complex components and excellent mechanical properties. However, during the SLM fabrication process, warping deformation often occurs in overhang regions due to insufficient support beneath them. This issue significantly compromises the dimensional accuracy, surface quality, and mechanical properties of the parts, and in severe cases, it even leads to manufacturing failure. This paper systematically reviewed the formation mechanisms and control methods of warping deformation in SLM-fabricated overhang structures, focusing on its effects on formed parts, underlying causes, influencing factors including energy parameters, scanning strategies, scanning speed, structural parameters, support design and optimization strategies. The recent advances in advanced control techniques such as intelligent compensation and numerical simulation were summarized. Emerging research directions including artificial intelligence-based process decision-making and multi-sensor in-situ monitoring were further prospected to provide theoretical insights and technical support for high-quality SLM fabrication of overhang structures.