Hydrological and meteorological data in Yantai port over twenty years are analysed. The mechanism of the genesis of storm surge and its general characteristics are studied mainly in view of the combined meteorological and oceanic influences. Applying the hydrological observations from 1980 to 1992 and the products of numerical weather forecast,the storm surges on different weather type are classified, and the factors are selected to build objective, quantitative, automated forecast system for storm surge. It had been proved to be useful such the system was used in service of Yantai Maritime Meteorological Observatory.