During the launch process of the electromagnetic railgun, the armature and the rails are in the state of high-current ultra-high-speed sliding electrical contact, with complex multi-field coupling effects involving electricity, magnetism, heat, and force occurring between them. Under the intricate interplay of complex mechanisms, the rails are prone to various damage phenomena such as grooving, gouging, transition, arc ablation, friction and wear, which seriously affects the overall performance and core indicators of electromagnetic railgun, including rail lifespan, launching accuracy and launching efficiency. This constitutes one of the core issues hindering the progression of electromagnetic railgun towards engineering applications. The research conducted by domestic and international researchers over recent decades on the damage phenomena and mechanisms of electromagnetic railgun are comprehensively summarized. Some novel approaches and methods for mitigating rail damage are analyzed and proposed, which offering theoretical foundations and empirical support for advancing the technological development and engineering applications of electromagnetic railgun.