Based on the monthly rainfall of 170 stations over Huaihe River Basin, NCEP reanalysis data and ERSST sea surface temperature data, the stability of the variation characteristics of the relationship between El Ni〖AKn~D〗o/La Ni〖AKn~D〗a and the summer rainfall over Huaihe River Basin is studied by using sliding correlation, composition analysis etc. It shows that the relationship between El Ni〖AKn~D〗o/La Ni〖AKn~D〗a and the summer rainfall over Huaihe River Basin is not stable, the 11year slide correlation probably mutates in 1979.It is significant negative correlation between El Ni〖AKn~D〗o/La Ni〖AKn~D〗a and the summer rainfall over Huaihe River Basin during 1961-1979, and it is normal correlation during 1980-1992, but it is significant positive values during 1993-2015. The influences of El Ni〖AKn~D〗o/La Ni〖AKn~D〗a on the precipitation over the Huaihe River Basin during two obvious correlation periods are mainly discussed. The influences of El Ni〖AKn~D〗o/La Ni〖AKn~D〗a on the precipitation over the basin during 1961-1979 and 1993-2015 are on the opposite. And the El Ni〖AKn~D〗o/La Ni〖AKn~D〗a events during 1993-2015 as a predictor of the summer precipitation over the Huaihe River Basin are weaker than the El Ni〖AKn~D〗o/La Ni〖AKn~D〗a events during 1961-1979. The influence of El Ni〖AKn~D〗o events on the precipitation over Huaihe River Basin is obvious, but the influence of La Ni〖AKn~D〗a events is not obvious, and the influences of both are asymmetrical. The distribution of Asian atmospheric circulation in El Ni〖AKn~D〗o developing (decaying) summer during 1961-1979 is conductive to the north and south air convergence (divergence) over the Huaihe River Basin, which makes the precipitation over the basin more (less) than normal. While the El Ni〖AKn~D〗o events are on the opposite during 1993-2015.