Firstly, the authors introduce the development process of Yunnan Seismic Monitoring Network (YSMN).Accumulating massive observation data with high quality for a long time is the basis of studying the physical process of earthquake and internal earth structure. Finally, the authors analyze the time and spatial distribution characteristic of Yunnan M≥5.0 earthquakes activities since 20th century, and it is the important reference on analyzing the earthquake activity and strong earthquake risk in Yunnan Province.oft-com:office:office" />