Abstract: In this paper, it is investigated that the time and space distribution of aftershocks within a very short time after a series of large and moderate earthquakes occurred in China during the last several years. The results show that for various earthquake sequences, there are sensible differences in the attenuation of the frequency and the variation of aftershock region within a very short time after large earthquakes. The present author believes that these differences may provide one of the evidences for judging the seismic sequence type and earthquake tendency after a large shock.