Abstract: This papeer analyzes the characteristics of seismicity before the Puer earthquake with M_s6.3 on January 27, 1993, and the afrershock sequence type.It is found that the seismic activity was quiet in the epicentral region and in its seismic belt,but increased in its neighboring seismic belt,one year before the Puer earthquake.There are different characteristics between the Puer earthquake and other moderately strong earthquakes occurred in this area before.The earthquake is a typical main shock-aftershock type revealed by each parameter of the aftershock sequence.