Microbial contamination arising from pathogens poses serious threats to human health and in recent decades has presented an unprecedented challenge to antibacterial research. Of the various antibacterial agents that effectively kill pathogens, halogen-based antibacterial compounds have been successful in eliminating harmful pathogen-associated diseases and are becoming the most popular disinfectants. As a significant subcategory of halogen antibacterial agents, N-halamines have drawn increasing research interest into their chemistry and practical applications. N-Halamines have many advantages over other antibacterial agents, including effectiveness against a broad spectrum of microorganisms, long-term physicochemical stability, high structural durability, and the regenerability of their functional groups, with corresponding renewal of their antibacterial properties. This review examines recent progress and research trends in both theoretical and experimental studies of N-halamines, with the aim of providing a systematic and comprehensive survey and assessment of the significant advances in our understanding of antibacterial N-halamines. This review serves as a practical guide to developing N-halamines through both broad and in-depth basic research and offers suggestions for their potential future applications.