Abstract: Seafloor geodetic datum network will be an important component of the new generation of national comprehensive PNT (Positioning, Navigation and Timing) system construction and the infrastructure of the future marine stereoscopic observation system. Global Navigation Satellite System-Acoustic (GNSS-Acoustic) technology can be used for high-precision underwater positioning and directly serves the construction of the submarine geodetic datum network. Focusing on the seafloor geodetic datum construction technology, this work summarizes the underwater acoustic navigation and positioning technologies and systems, and the key points of the station site selection and its deployment and recycling for the construction of seafloor geodetic datum are also analyzed. Based on the discussion of the GNSS-Acoustic observation platform and data acquisition, the research progress of the data processing methods of GNSS-Acoustic positioning is emphasized. Finally, the current main applications of GNSS-Acoustic positioning are briefly summarized, and the technical requirements and application problems of future seafloor geodetic datum construction are presented.