The Fujian-Guangdong coastal earthquake zone has the highest seismicity level in southeast coastal region of China.The region where economy is flourishing and density of population is very large is the most famous home of foreign residents of our country.Therefore,thoroughly studying the Niushan Island Brother Islets fault zone and its activity has important significance to earthquake prediction,earthquake disaster reduction and seismic safety evaluation of some great engineerings in the region.The study results show that M_S≥7 earthquakes will possibly occur along the fault zone in the future.