By using GODAS monthly mixed layer depth(MLD) and 160-station monthly precipitation data in China,the seasonal and interannual characteristics of MLD are analyzed over the north Pacific,along with the influences of MLD interannual anomaly on summer rainfall in China discussed.The results show that:1) The MLD is the deepest over the latitudes from 30 to 40°N and is larger in winter and spring than in summer and autumn.2) The interannual anomaly is most prominent over the middle part of the north Pacific near the international date line in four seasons;but only the MLD anomaly is somewhat related to ENSO in summer,and MLD is of interdecadal anomaly characteristics in autumn,winter and spring.3)When MLD increases over western and middle part of the north and central area of Pacific in the previous winter,the precipitation may decrease over the part of the lower Yellow River,Huang-huai,Jiang-huai and to the south of the Yangtze River reaches(except the south of Guangxi) and the precipitation may increase in He-tao,east part of Neimeng and most part of Northeast China in the following year.