Abstract: The sealing of underground drilling holes in coal mines constitutes a critical control link for ensuring coal mine safe production, achieving efficient gas extraction, and preventing water inrush hazards. The hole sealing technology, drilling hole packer, and sealing materials represent the fundamental technical basis and core equipment required to ensure borehole sealing quality. The current research status of underground coal mine borehole sealing processes was systematically reviewed and analyzed from multiple perspectives, including application scenarios, structural principles of drilling hole packers, characteristics of sealing materials, and technological features of sealing processes. For different hole sealing technologies, the corresponding drilling hole packers, technological orientations, and application purposes were systematically summarized, and the process characteristics of various drilling hole packers were comparatively analyzed. Furthermore, the properties, existing limitations and applicable scenarios of commonly used sealing materials in underground coal mines, including cement-based materials, polyurethane-based materials, and gel-based materials, were comprehensively summarized. Finally, future research priorities and development directions for underground borehole sealing in coal mines were discussed from four key aspects: theoretical research on hole sealing principles, structural optimization and technological innovation of drilling hole packers, the development of novel sealing materials, and the advancement of intelligent and automated hole sealing equipment.