With the expansion of human engineering activity both in scale and in sphere, there appears an accompaning new problem——induced seismicity in these decades especially in the last two decades. Many activities would intensify seismicity, such as impoundmen water in reservoir, large scale opencut mining and underground mining 9 waste liquid disposal,geothermal power generation as well as filling of high pressure water into the ground for a second time of petrolium exploitation, large scale drawing of underground water in cities and the post effect of underground nuclear detonation, ets. Since induced seismicity are accompanying engineering projects and occur near the large engineering projects triggering them, obvious social and ecnomic consequences would be incurred.therefore even as weak as M=5 magnitude, an earthquake has to be taken into account. Among various kinds of induced seismicity already known, reservoir induced seismicity (usually called reservoir earthquake) is most worth heeding. The Xinfengjiang Reservoir in China, the Kremasta Reservoir in Greese, the Kariba Reservoir in the border area between Zambia and Zinbabwe and the Koyna in India, all had triggered strong earthquakes of more than 6 magnitude one after another in 1960s, and such earthquake is most serious in Xinfengjiang and Koyna.