By analyzing the forecast opinions and forecast data before the Mojiang M_S5.9 earthquake,we found that the M ≥ 5.5 earthquakes in Yunnan are calm and abnormal,and the M ≥ 5.0 earthquakes have a continuous interval of more than 200 days. The small magnitude of the two earthquakes with M5.0 in Tonghai is a significant feature of seismic activity anomalies before the earthquake. The indication significance of the Tonghai earthquake and the precursory anomaly M ≥ 5.7 earthquake medium and M ≥ 5.0 earthquake short-term compre￣hensive forecast index is the main basis for judging the short-term risk of earthquake. Since 1900,the M ≥ 5.0 earthquakes in the 50km range of Tonghai has shown M ≥ 5.0 seismic superiority correspondence and the regional surface strain variation characteristics of GNSS characterization,which provide clues for location determination. The forecast experience and data of the Mojiang M_S5.9 earthquake enriches our understanding of the complexity of earthquakes and accumulates new information for earthquake case study.