Objective To analyze the effects of change water sources on population iodine nutrition and goiter status in historical high water-iodine area in Yufa Town of Daxing District,Beijing,and evaluate the control effects.Methods A retrospective analysis method was used to collect epidemiological survey data such as water iodine content,urinary iodine content and goiter rate before and after iodine reduction in Yufa Town of Daxing District,Beijing,2005-2016,and the data were compared and analyzed.Results Yufa Town had implemented water reform since 2005.As of 2015,8 change water source projects had been built,and all historical high-water iodine villages had completed drinking water transformation.Totally 64,12,26,26,and 37 water samples were collected and tested in 2005,2009,2010,2011,and 2014,the medians of water iodine were 185.2,20.9,14.1,16.8,and 21.6 μg/L,respectively,and the medians of water iodine decreased significantly through changing water source.Totally 148,153,150,and 40 urine samples of children aged 8 to 10 years old were collected and tested in 2005,2009,2011,and 2016,the medians of urinary iodine were 520.1,201.6,143.0,and 135.0 μg/L,respectively,and the medians of urinary iodine decreased to a suitable range (100-199 μg/L) through changing water source.Totally 154,292,40,and 40 school-age children were tested for thyroid volume in 2005,2009,2011,and 2016,and 10,6,0,and 1 thyroid enlargements were detected,respectively.The thyroid enlargement rates were 6.49％.2.05％,0,and 2.50％,and the rates of goiter were reduced to less than 5％ through changing water source.Conclusion The high water-iodine in water-borne high iodine area in Yufa Town,Daxing District,Beijing is basically eliminated after change water sources,water improvement to reduce iodine is a basic measure to control high iodine damage in high water-iodine areas.