Abstract: Heavy metal pollution has been a serious problem facing rivers worldwide because of its persistence, toxicity and bioaccumulation. As the largest river in China, Yangtze River plays an important role in providing water, mitigating flood, and maintaining ecological balance. Therefore, it is of great importance to study its metal pollution status. As is a carcinogenic heavy metal and one of the most important pollutants in the Yangtze River. In this study the spatial distribution and health risk of As in riverside water of Yangtze River were assessed. The results showed that As concentration increased from upstream to downstream generally. The comparison with existing studies indicated that As concentration in Yangtze River showed a decreasing trend. However, special attention should be paid to sites(such as sites of 52, 43, 42, 51, 78, 81) where As showed high cancer risk. Water temperature and ion concentration may be important factors affecting As toxicity. This study provides a basis for the treatment and protection of water environmental pollution in Yangtze River.