Description: GNSS continuous observation enables us to rapidly estimate a finite fault model for a large earthquake without saturation of magnitude. Geospatial Information Authority of Japan (GSI) operates a dense and nationwide GNSS continuous observation network named GEONET, which is capable of providing 1Hz displacement data in real-time. After a gigantic 2011 earthquake in Japan, GSI in collaboration with Tohoku university launched a REGARD (REal-time GEONET Analysis system for Rapid Deformation monitoring), which offers a finite fault model based on the real-time displacement data observed in GEONET. The REGARD system has successfully provided the co-seismic displacement and finite fault model information for recent M~7 or larger earthquakes. These results are provided to government agencies in a few minutes from an earthquake occurrence and are taken advantage of their initial response and tsunami prediction. To achieve the highest reliability in REGARD, we seek the possibility of applying precise point positioning (PPP) instead of the current relative positioning. PPP can improve the robustness of the real-time positioning subsystem in REGARD by its nature of single positioning. The precise satellite orbit and clock information is generated using MADOCA developed by Japan Aerospace Exploration Agency (JAXA). The satellite orbit and clock includes not only GPS and GLONASS but also QZSS, the Japanese satellite positioning system. In our performance assessment, PPP showed a cm-level accuracy, which is close to the performance of RTK.