Objective To understand the distribution of iodine content in drinking water in Yunfu City,so as to provide a basis for accurately delineating iodine deficiency areas,suitable iodine areas and water-based high iodine areas,and to provide guidance for implementing scientific iodine supplementation and prevention policies in various regions. Methods In Yunfu City,drinking water samples (including centralized water supply,decentralized water supply,and mixed water supply) were collected from permanent residents in all counties (cities,districts) based on administrative villages (communities).The iodine content in the water was detected,and the median iodine content in the water was calculated. Results In 2022,a total of 6 017 water samples were collected in Yunfu City,with a median iodine content of 2.00 μg/L,ranging from 0.20 to 322.00 μg/L.Among them,97.56% (5 870/6 017) water iodine was < 40 μg/L,1.98% (119/6 017) water iodine was between 40 and 100 μg/L,and 0.46% (28/6 017) water iodine was >100 μg/L.In 973 administrative villages (communities),the median water iodine ranged from 0.20 to 68.70 μg/L.Among them,972 administrative villages (communities) with median water iodine was less than 40 μg/L,accounting for 99.90%,and 1 administrative village (community) with median water iodine between 40 and 100 μg/L,accounting for 0.10%. Conclusion Yunfu City is an iodine-deficient area on the whole.The iodine content of drinking water in most areas is at a low level.Scientific iodine supplement should be adhered to and iodine deficiency disease monitoring should be carried out continuously.