The interannual and interdecadal variability of East Asian summer monsoon and its impacts on summer precipitation over the Songhuajiang-Nenjiang River basin are investigated based on NCAR/NCEP reanalysis data and 39-station rainfall data from 1951 to 2000. The results show that both East Asian summer monsoon and the rainfall over the Songhuajiang-Nenjiang River Basin possesses the variation periods of 3 - 5 and 10 - 12 years. Two climatic jumps occurred at the end of the 1960s and the beginning of the 1980s, respectively. East Asian summer monsoon significantly influences the rainfall over the Songhuajiang-Nenjiang River basin. In addition, factors such as the westerly and the Western Pacific subtropical high have also impacts on summer rainfall over the Songhuajiang-Nenjiang River basin.