The addition of flame retardants typically reduces the mechanical properties of polyamide (PA). Consequently, enhancing the flame retardancy of PA while maintaining its high mechanical performance has become a key research focus in flame-retardant modification. This review summarized recent advances in the high-performance modification of halogen-free flame retardant PA, primarily including intrinsically flame retardant PA, the addition of macromolecular or nanoscale flame retardants, and reactive chain-extending flame retardant modification. This article introduced the synthesis of flame retardants, analyzed the effects of flame retardant structure and content on the flame retardancy and mechanical properties of PA, and elucidated their corresponding flame retardant mechanisms. The development trend of high-performance halogen-free flame retardant PA was further prospected.