Abstract: The anomalies of the sea surface tem perature in the central and eastern tropical Pacific kept the positive values for more than 4 years from 1991 to 1994. On this background, the Ninño3 index assumed two oscillations. As the result, there were three warm episodes during this period. In this paper, a diagnostic study of the basic features of the sea surface temperature and wind fields in tropical Pacific has been done. It is found that two anomalous processes of negative SST anomalies in the eastern equatorial Pacific between 5°S-5°N existed. The narrow cold water tongue in the equatorial zone has strong temperature gradient and surrounded by the off-equatorial warm waters, with one positive SSTA area located in the middle-latitude of the Northeast Pacific and the other in the Southeast Pacific. The cold water looks like a cold core. This anomalous features of the SST A evolution during 1991 to 1994 is different from those observed in the history. Based on a EOF analysis, the distribution of the first eigenvalue (EOF1) just reflects the cold core pattern. Using the low-fre-quency filter, the LF component of the Ninño3 index showed the positive anomaly for 4 years, but the cross-section of the SSTA along the equator has two periods of negative SSTA near the equatorial East Pacific. However, the low-frequency componentof the zonal wind along the equator only demonstrates one cycle. There are the westerly zonal wind anomaly over the tropical central Pacific from 1991 to June of 1992, and easterly wind anomaly from July 1992 to the end of 1994. It is noticeable that the easterly anomaly of zonal wind did not extend to the tropical eastern Pacific. It can be found the strong westerly zonal wind anomaly at 850 hPa off the coast of tropical South America. These results suggest that the coupled system of the Pacific Ocean and the at mosphere has evolved as a whole ENSO cycle during this 4 years. The warm phase spanned from Jan., 1991 to June, 1992, and the cold phase from July, 1992 to the end of 1994. But, this La Nina phase has been aborted by the positive anomalous SSTA in the middle-latitude off East Pacific, which were linked with the adjustment of the Walker cell and Asian monsoon.