Abstract: Based on 5o×5o latitude-longitude grid SST departure data, which was edited by UK and MIT in 1990 for the years of 1968~1977 and 1982~1983, the monthly global SST departure composite analyses for four El Nino events and three La Nina events during the two periods have been conducted. The results show that some warming low-frequency fluctuation centers travel obviously eastward along the equator during onset phase of El Nino event, while stable strengthening cold centers extend westward along the Pacific coast of South-North America during onset phase of La Nina event.