<p>High nitrogen steel (HNS) is an advanced engineering material characterized by an exceptional combination of high strength, high toughness, excellent corrosion resistance, low magnetism, and good biocompatibility. These superior properties make it particularly suitable for demanding applications in critical fields such as marine engineering, nuclear energy equipment, medical implants, and national defense systems. Based on the latest international research progress, this paper systematically reviews the status and technical characteristics of mainstream joining technologies for HNS, including the fusion welding, friction stir welding (FSW), and brazing. The study focuses on key aspects of HNS welding, such as the shielding gas atmosphere, heat input control, welding filler material selection, and critical parameter optimization. Furthermore, it conducts an in-depth analysis of the process control mechanisms and their effectiveness in existing welding methods for HNS, identifies shortcomings in current research on HNS joining systems, and outlines future prospects. The primary objective of this paper is to consolidate current knowledge and provide a reliable reference and theoretical foundation for advancing research and industrial applications in the field of HNS welding.</p>