Abstract: Extreme heat waves have become more frequent and intense as a result of global warming, posing a serious threat to human health and to the sustainability of society as a whole. Using meteorological data and social statistics, a set of quantitative indicators is developed to quantify the temporal and spatial characteristics of heatwaves across 1 067 counties within the Yangtze River Economic Belt, including high-temperature days, high-temperature intensity, heat wave frequency, heat wave duration and heat wave intensity. In addition, an evaluation index system based on “exposure-sensitivity-adaptability” is being conducted to assess the vulnerability to heat waves. Afterwards, a spatial distribution map of heat wave vulnerability is developed, and the causes of heat wave vulnerability are explored. Based on the results, it can be concluded that: (1) Events of high temperatures and heat waves within the Yangtze River Economic Belt appear to share a similar pattern of “one belt and one point”; (2) The exposure index to heat waves within the Yangtze River Economic Belt shows a clear tendency to decrease northwest to southeast, but the spatial distribution of the sensitivity and adaptability index within the region is fragmented. The vulnerability index exhibits a clear spatial agglomeration characteristic, despite the absence of obvious spatial agglomeration characteristics; (3) In the analysis of brittle types, 67.4% of the counties are vulnerable as a result of a lack of adaptive capacity, followed by 24.5% of the counties vulnerable due to extreme heat waves, and only 8.1% of the counties vulnerable due to sensitivity. In contrast to the west, which is less vulnerable and brittle due to a lack of adaptability, the eastern and central regions are more vulnerable and fragile as a result of high temperature exposure. Accordingly, the results of this study may provide a scientifically sound basis for preventing extreme heat wave disasters and increasing adaptability to heat wave events in the future.