Abstract:Based on NOAA daily sea surface temperature(SST) data, NCEP/NCAR daily wind and specific humidity field data, and the daily rainfall data from National Meteorological Information Center of China, the low frequency cycle of climatological SST over the northwest Pacific is discussed, and the relationship between ISO(intraseasonal oscillation) SST over the northwest Pacific and ISO rainfall anomaly in eastern China in summer is also investigated.Results show that the most significant regions of ISO precipitation anomaly in eastern China affected by ISO SST anomaly over the northwest Pacific in summer are the middle reach of Yangtze River and the coastal areas of South China, the Yangtze-Huaihe regions, and most of North China.The wave train with the structure of cyclone-anticyclone-cyclone(anticyclone-cyclone-anticyclone) from south to north along East Asia coast is caused by the interaction between ISO SST over the northwest Pacific and 850 hPa circulation field, which leads to vapor convergence or divergence over East Asia coast and induces the summer ISO rain belt advancing from Yangtze-Huaihe regions to North China(retreating from North China to the middle reach of Yangtze River and the coastal areas of South China).