Abstract: In this paper, the strong seismic activity regions during earthquake preparation and immediately before earthquake are studied by "dynamic stress ellipse" method which is derived from both the centres of gravity of spatial distribution patterns of notable earthquakes in defferent time stages before strong earthquakes in North China and optimum fracture points which are obtained by "golden section" method.Through some examples, it is considered that the "dynamic stress ellipse" method can be applied to tendency predict ion and it can provide a useful basis for semi experience and semi-quantitative long-term, mid-term and short-term estimation of future strong seismic activity regions.It is considered that the formation of such patterns is mainly the result of "lynam ic energy balance" of seismic block or seismic belt.