With the construction and planning of the Sichuan-Tibet Railway and the Strait Tunnel, the tunnel construction has further deepened into the former engineering geological forbidden area, and a large number of large buried depths and long hole line tunnels have emerged. The problems of extremely high water pressure, strong permeable strata, high ground stress, high ground temperature, and high active faults are becoming more and more prominent. As a direct means of geological disaster management, grouting can effectively change the physical and mechanical properties of the stratum, carry out anti-seepage reinforcement of the surrounding rock, ensure the safe development of resources, and greatly reduce the impact of a complex geological environment on engineering construction. This paper summarizes the research status and development trends of splitting grouting domestically and abroad in recent years, splitting grouting materials and equipment, numerical simulation calculation, and key technologies that need to be broken through. The development status and trend of key technologies of splitting grouting are analyzed from the above four aspects. The grouting theory, materials, equipment, and effects inspection methods are mainly analyzed and discussed. Based on the research and development of existing key technologies, it is of great significance to further deepen the research on grouting theory, innovate and optimize grouting technology, develop and prepare grouting materials, customize supporting drilling and grouting equipment, and quantitatively determine grouting effects to promote the sustainable development of tunnel grouting technology. This review can provide a new perspective and basic data for academic research in the field of grouting in geotechnical engineering.