Abstract: The El Nino phenomenon is currently a focus of attention in the international community. By use of the existing achievement in scientific research both home and abroad, on the basis of air-sea interactions, the genesis mechanism of the El Ni o was put under examination, such as the role of Walker circulation and trade winds, the East Asian deep trough in summer, the tropical atmospheric circulation anomalies; in combination with the statistical data of air-sea Correlation in the prievious many years, a correlation analysis of precipitation in China and the El Nino phenomenon was done to find out the coupled relation. Finally, based on modern technology, a prediction of the future atmospheric and oceanic observations was made as well.