Abstract:With the NCEP/NCAR reanalysis data during 1961-2011 and the precipitation data from 45 stations in the Yellow River Basin, Nino3 SST difference index (ΔI SST3) from the previous October to current April is defined and the relationship between ΔI SST3 and summer sea surface temperature, and the correlations of atmospheric circulation and summer precipitation in Yellow River Basin with the Δ I SST3 index are analyzed. The results show that: (1) When ΔI SST3 increases (decreases), the following summer’s sea surface temperature of the central and eastern equatorial Pacific tends to be warm (cool) while that of the area from South China Sea to Philippines Peninsula sea region tends to be cool (warm). (2) The Δ I SST3 also shows a significant negative correlation with the subtropical area within 100°E-80°W at the 500 hPa height field. The positive and negative abnormal difference field of Δ I SST3 shows that when the Δ I SST3 increases (decreases), the height at 500 hPa over the tropical and subtropical Pacific regions in summer is lower (higher); the 850 hPa westerly (easterly) to the north of the equator appears to be abnormal; the Western Pacific subtropical high is significantly weak (strong); northerly (southerly) airflow prevails in coastal areas of eastern China; warm and humid airflow is inactive (active); the monsoon is weaker (stronger). However, the Mongolia cyclone (anticyclone) in the middle and high latitudes is further developing. As a result, the anticyclonic (cyclonic) circulation covers the Hetao Region.(3) The ΔI SST3 and the summer precipitation over the Yellow River Basin share a significant negative correlation with a coefficient of -0.51. When the Δ I SST3 is positively abnormal,the summer precipitation in the Yellow River Basin is likely to decline; When the Δ I SST3 presents negative anomaly,precipitation of the Yellow River basin in summer tends to exceed the normal, and the negative anomaly has more significant influence on the summer precipitation of the Yellow River Basin.