This paper collects and files the data of all the 13 observation wells for underground within a radius of 700km from the Yushu MsT. 1 earthquake on April 14, 2010, and analyzes the number of the data which are more than three times of the mean square deviation of the month overproof from May, 2008. It is found that the number of month overproof increased in ten wells six months before the earthquake, four wells increased coseismicly and after the event. The similar phenomena were also found before the two earthquakes with M 6. 0 in the Dachaidan region from 2008. Those abnormal phenomena may reflect the interaction of the field precursor and the source precursor before the Yushu earthquake.[著者文摘]