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An analysis is made of the relation between summer precipitation and antecedent circulation by using NCAR/NCEP 500hPa reanalysis data and summer precipitation data from central North China from 1957 to 2002. The results show that there is obvious correlation between summer precipitation, the intensity of winter East Asian Trough and the spring height field over the Mongolia Plateau from Balkhash to Baikal. Winter East Asian Trough was stronger and the height over the Mongolia Plateau in spring was lower than normal before the middle 1980s, but vice versa after 1985. The trend is consistent with the variation of summer precipitation. It is demonstrated that the reasons for summer precipitation decrease include the weakened winter East Asian Trough and higher spring Mongolia Plateau height field. When the winter East Asian Trough is strong, the summer West Pacific Subtropical High is strong over the Japan sea region correspondingly, which is favorable for the increase of summer precipitation over the central North China. When the heights of the spring Mongolia Plateau height field are higher, it is favorable for the occurrence of the circulation pattern “high in the west and low in the east," in which lessthannormal summer precipitation in central North China is likely to happen.