Objective To investigate fluorine content in water and prevalence of dental fluorosis of children in drinking-water type fluorosis areas in Yongqiao district, and provide the basis for formulation of water defluoridation measures in 13th Five-Year planning. Methods Determinating results of fluorine content in water and situation of dental fluorosis in children aged 8-12 from 105 endemic fluorosis villages in 16 monitoring townships based on the application of the census. Results The water fluoride average ranged in 0.59-1.41mg/L in 16 monitoring townships. 2162 patients with dental fluorosis were found in 13936 children aged 8-12 include 1695 very mild cases(12.16%), 446 mild cases (3.2%), 20 moderate cases(0.14%), 1 severe cases(0.007%) and no defect of dental fluorosis cases, and the dental fluorosis index was 0.39. The detection rate of dental fluorosis of 8,9,10,11 and 12 years old group were 13.74%, 17.21%, 16.72%, 14.64% and 15.60%. There were significant differences in the detection rates of all age groups (χ²=19.09,P<0.01). Conclusion There are 105 endemic fluorosis villages in part of which were with highei prevalence of dental fluorosis of children. There is a big gap to the planning control targets in 12th Five-Year, so the quality of local drinking water should be further improved to effectively control water fluoride and dental fluorosis.