Abstract: In this paper, three topics are selected to be presented as representative of Mei Shirong's research on seismicity. The proposal of North-south Seismic Belt promotes the study of deep and shallow tectonics, and the discovery of Longzhiba Fracture Zone has important geotectonic significance. The phenomena of seismic gap and epicenter migration are analyzed, examples of seismic echoes between the North-South and South Asian seismic belts are given, and the mechanical mechanisms are described. The correct judgment of direct foreshocks and precursor seismic swarms is very important in earthquake prediction. The characteristics of direct foreshocks are introduced, and the distribution of seismic swarms in mainland China is given.