This paper relates to the recent and present rupture activities in the maximum intensity area of the Huaxian great earthquakes(M=8.0,Jan. 23,1556)and makes an analysis of neutectonic stress field.It tells the tectonic sites where the earthquake occurred,estimates the period of earth-quake occurrence in this area and probes by means of the finite element method into the relation between the underground stress and the Huaxian gear earthquake.