The ecological risk of cadmium in five representative stations in the Upper Yangtze River Rare Fish Nature Reserve was evaluated based on the risk quotient model（RQF）of Cadmium in Freshwater Aquatic Quality Criteria（2020 Edition）issued by the Ministry of Ecology and Environment.The results show that：（1）the annual average values of short-term water quality criteria（SWQC）at Ping Shan Station，Yibin Station，Luzhou Station，Gaochang Station and Fushun Station were 6.89μg/l，6.68μg/l，6.51μg/l，6.26μg/l and 10.49μg/l，respectively；and （2）the annual average values of long-term water quality criteria（SWQC）at Ping Shan Station，Yibin Station，Luzhou Station， Gaochang Station and Fushun Station were 6.89μg/l， 6.68μg/l， 6.51μg/l， 6.26μg/l and 10.49μg/l，respectively.The annual average values of the long-term water quality criteria （LWQC）are 0.30μg/l，0.30μg/l，0.29μg/l，0.28μg/l，and 0.38μg/l.（2）Short-term risk at Luzhou station is 0.30μg/l，0.30μg/l，0.29μg/l，0.28μg/l，and 0.38μg/l，respectively.The SRQ of Ping Shan Station，Yibin Station，Gaochang Station and Fushun Station are 0.31，0.35，0.37 and 0.23 respectively，which are all in the medium grade.The annual average long-term risk quotient（LRQ）values at Ping Shan Station，Yibin Station，Luzhou Station，Gaochang Station and Fushun Station were 7.14，7.56，1.06，7.99 and 6.34 respectively，which were all at the “high” level. （3）The main factor influencing the ecological risk of cadmium is the total hardness of the water body in the Upper Yangtze River Rare Fish Nature Reserve.（4）This study found that in the Upper Yangtze River Rare Fish Nature Reserve，there are a number of measuring stations SRQ31 high-risk situation，the relevant departments of the southwest and south of the Sichuan mining，smelting enterprises，mining，transportation and sewage discharge to carry out the necessary remediation.At the same time，strengthening the monitoring and early warning of cadmium content and total water hardness should be one of the priorities of water resources management in protected areas in the future.