Climate change index is one of advanced issues in climate change research. There exist many specific indices in climate change research in China and other countries, but comprehensive indexes are very rare. So in this paper, a comprehensive climate change index (CCI) is defined based on single factor of temperature and precipitation index to assess the sensitivity of climate change, and the comprehensive information about climate change is obtained. Because the index size represents the difference in frequency between before and after extreme climate events around abrupt climate change, reflecting the ability for one region to respond to climate change and the sensitivity to the climate change, the index indicates a variety of information about climate change and can provide a certain judgment basis to better deal with extreme climate events. According to the CCI, the climate change and its regional sensitivity in China in recent 50 years are discussed. The results show that Inner Mongolia, northeast central, northwest and central Yunnan have higher CCI indexes, which indicates that the extreme climate events in these regions happen more frequently after the abrupt climate change. The mean CCI is computed of all stations in each province in China, showing that South China and east part of Southwest China each have a minimal index, indicating that these areas are not sensitive to climate change; in the North and Northeast China extreme events happen frequently. Climate change is obvious in high latitude and tropical and subtropical regions, the North and Southwest China are more sensitive, while the South of the Yellow River is less sensitive. The coastal areas with relatively high CCI have strong sensitivities due to the heavy rainfall influence from monsoon and typhoon.