El Niño events developed in the equatorial central-eastern Pacific in the spring of both 1991 and 1997. The former began in May and the latter in April. However, a dry summer occurred over the Huanghe-Huaihe valley in 1992, but a wet summer prevailed in 1998. Also, the summer circulation anomalies showed different patterns over the Eurasia-Northwest Pacific region between 1992 and 1998. In the summer of 1992, the Northwest Pacific subtropical high (NWPSH) shifted eastward and the blocking high activities over the Eurasian midlatitudes were weaker than normal, resulting in below-normal rainfall anomalies over the Huanghe-Huaihe valley. In contrast, the NWPSH shifted westward and the blocking high activities over the Eurasian midlatitudes were intensified in the summer of 1998, leading to a wet summer over the Huanghe-Huaihe valley. Further diagnosis and model experiment results indicate that the contrasting pattern of summer rainfall anomalies over the Huanghe-Huaihe valley between 1992 and 1998 was probably due to the Northwest Pacific convection activities anomalies, as well as SST anomalies over the Sea of Okhotsk, its adjacent region, and the midlatitudes of the North Atlantic. The summer Northwest Pacific convection activities were intensified (weakened) in 1992 (1998), which favored an eastward (westward) shift of the NWPSH. Additionally, the warm SST anomalies over the Sea of Okhotsk and adjacent region favored the intensified blocking high activities, whereas the warm SST anomalies over the midlatitudes of the North Atlantic favored the intensified blocking high activities over the Urals. These results reveal that a large proportion of the interannual variability of the summer rainfall anomalies over the Huanghe-Huaihe valley cannot be explained solely by the El Niño signals; rather, it is also related to the Northwest Pacific convection activities and SST anomalies over the Sea of Okhotsk and the midlatitudes of the North Atlantic. Therefore, the combined effect of multiple factors should be considered for improving the predictability of summer rainfall anomalies over the Huanghe-Huaihe valley on the seasonal to interannual timescale.