Long-term forecast of large earthquakes is an important application of earthquake science to promote earthquake preparedness of people and disaster mitigation. The Earthquake Long-Term Forecast Panel was newly organized as one of the program promotion panels under the 2nd Earthquake and Volcano Hazards Observation and Research Program during 2019–2023. The panel has been promoting studies that advance long-term forecasts of large earthquakes by sharing research prospects and exchanging information on related research topics. The program emphasized developing new long-term forecast methods based on the observation data including geodetic and seismicity data and the physical and statistical models, which lead to not only probabilistic forecasts, but also the development of possible scenarios for major earthquakes at the present. In addition, paleoseismological studies in terms of geological and geomorphological studies as well as archaeological and historical studies were conducted. Some results of the earthquake occurrence history were reflected in the official long-term evaluation by the Headquarters for Earthquake Research Promotion. It is evaluated that our study advanced under the program in the last five years. However, the 2024 M_JMA7.6 Noto Peninsula earthquake and other earthquakes that occurred in this program term have raised several problems in earthquake science and hazard mitigation, and it is important to continue and further develop our research in the next program.

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