By use of monthly rainfall data of June-August from 1951 to 1999 in 17 meteorological stations in North China,the severe flood and drought years are graded with the method of Z index.Results show that the severe flood years are 1954、1956、1963、1964、1971、1973 and 1996;the serious drought years are 1968、1972、1983、1986、1989、1992、1997 and 1999.Then the interdecadal variation of summer drought/flood in North China is discussed.In addition,the spatial distribution of severe flood and drought in North China is investigated with EOF analysis and the relationship between North China summerprecipitation and North Arctic sea-ice in spring is also discussed.It is found that the summer rainfall bears a positive correlation to the extent of spring sea-ice.When there is larger(smaller) spring sea-ice extent,the summer rainfall is more(less).