Study of seismicity in fault zones, especially study of modern large earthquakes is important part of active tectonic research. As the study is going on, the area we concerned was from a single fault to the space consisted of several faults and fault-blocks, where the large earthquakes occurred. Recent tectonic activity of Bayankala fault-block is widely concerned after Wenchuan earthquake and Yushu earthquake. We considered the movement of Bayakala fault-block, analyzed its seismicity, their quasi-period, focal mechanism，their maximum magnitude, and the relationship between strike-slip faults in boundaries and large earthquakes, according to historic large earthquake records since 1900(Ms≥7). We suggest that:(1)there are three earthquake series since 1900, the Diexi-Huashixia earthquake series(1923-1937), the Dari-Luhuo earthquake series(1947-1976) and the Kunlun-Wenchuan earthquake series(since 1997);(2)the characteristics of quasi-period about the time interval among series and the period each series last is not obvious, because the difference between the Dari -Luhuo series and the other two can not be ignored, and the Kunlun-Wenchuan series is not over yet;（3）Bayankala fault-block has released major part of energy after Kunlunshan Ms8.1 earthquake and Wenchuan Ms8.0 earthquake, we can not image that there will be large earthquake (Ms≥8) in the short future;(4) strike-slip faults are major boundary faults which controlled the movement of Bayankala fault-block , and strike-slip earthquakes is the major part of each series;(5)India plate push north strongly influence the occurrence of large earthquakes in boundary faults.