Abstract. To quantify climate change impact and difference on basin-scale river runoff under the limiting global warming thresholds of 1.5°C and 2.0°C, this study examined four river basins covering a wide hydroclimatic setting. We analyzed projected climate change in four basins, quantified climate change impact on annual and seasonal runoff based on the Soil Water Assessment Tool, and estimated the uncertainty constrained by the global circulation models (GCMs) structure and the Representative Concentration Pathways (RCPs). All statistics for the two basins located in northern China indicated generally warmer and wetter conditions, whereas the two basins located in southern China projected less warming and were inconsistent regarding annual precipitation change. The simulated changes in annual runoff were complex; however, there was no shift in seasonal runoff pattern. The 0.5°C global warming difference caused 0.7°C and 0.6°C warming in basins in northern and southern China, respectively. This led to projected precipitation increase by about 2% for the four basins, and to a decrease in simulated annual runoff of 8% and 1% in the Shiyang and Huaihe rivers, respectively, but to an increase of 4% in the Chaobai and Fujiang rivers. The uncertainty in projected annual temperature was dominated by the GCMs or the RCPs; however, that of precipitation was constrained mainly by the GCM. The 0.5°C difference decreased the uncertainty both in the annual precipitation projection and the annual and monthly runoff simulation.