In the last half century, a significant warming trend occurred in summer over eastern China in the East Asian monsoon region. However, there were no consistent trends with respect to the intensity of the East Asian summer monsoon (EASM) or the amount of summer rainfall averaged over eastern China. Both of the EASM and summer rainfall exhibited clear decadal variations. Obvious decadal shifts of EASM occurred around the mid- and late 1970s, the late 1980s and the early 1990s, and the late 1990s and early 2000s, respectively. Summer rainfall over eastern China exhibited a change in spatial distribution in the decadal timescale, in response to the decadal shifts of EASM. From the mid- and late 1970s to the late 1980s and the early 1990s, there was a meridional tri-polar rainfall distribution anomaly with more rainfall over the Yangtze River valley and less rainfall in North and South China; but in the period from the early 1990s to the late 1990s and the early 2000s the tri-polar distribution changed to a dipolar one, with more rainfall appearing over southern China south to the Yangtze River valley and less rainfall in North China. However, from the early 2000s to the late 2000s, the Yangtze River valley received less rainfall.