Abstract: The study aims to analyze the abnormal cause of summer precipitation over the Songhua River Basin in 1998 and 2016 which were all strong El nino attenuation year, and improve the prediction ability of summer precipitation over the Songhua River Basin. Based on the daily precipitation data of 97 stations over the Songhua River Basin and NCEP/NCAR reanalysis data, the authors analyzed the abnormal cause of summer precipitation over the Songhua River Basin in 1998 and 2016 by a variety of physical diagnosis methods such as synthetic analysis, correlation analysis, etc. The results showed that: only the end time and intensity of the strong El nino event could not determine the summer precipitation change, the mid-high latitude circulation and its evolution in the atmosphere should also be considered, such as the intensity and occurred time of the northeast cold vortex and the variation of blocking high in Eurasian circulation. Taking into account the impact of SST and subtropical system, as well as the effect of abnormal variations of the mid-high latitude circulation on the summer precipitation, to diagnose and predict the summer precipitation over the Songhua River Basin from multiple factors could improve the forecast level, thereby, to serve the meteorological disaster prevention and reduction and agricultural production.